Australian batsman Travis Head has been ruled out of the fourth Ashes Test and returning a positive test for Covid-19.

Cricket Australia confirmed that the 28-year-old is asymptomatic and will not fly with the squad to Sydney on Friday for the fourth Ashes Test due to start at the SCG on January 5.

The remainder of the Australian squad, their families and the team's support staff have undergone PCR and RAT tests on Friday and are still planning to travel to Sydney on Friday.

A Cricket Australia spokesperson said: “As part of our testing procedures, we are PCR testing players, their families and our support staff daily. Unfortunately, Travis returned a positive Covid-19 result earlier today. Thankfully, he is asymptomatic at this stage. We anticipate that he will be available to play in the fifth men’s Ashes Test in Hobart.

“We are grateful to our exceptional medical staff for all the work they have done throughout this series and we will continue to work with and support the players, their families and staff from both teams.”

Mitchell Marsh, Nic Maddinson and Josh Inglis have joined the Australian squad as additional cover as a precautionary measure, although Usman Khawaja appears most likely to replace Head in the XI.

On Friday, there was a huge jump in confirmed Covid-19 cases in Sydney, were the fourth Test will be played, with 21,151 infections diagnosed up from 12,226 on Thursday.

The Boxing Day Test earlier this week was jeopardized after positive cases within the England camp, while Third Test match referee David Boon tested positive on Thursday.

Australia captain Pat Cummins missed the second Test in Adelaide after being a close contact of a confirmed Covid-19 case.

Head becomes the first player to miss a Test in the Ashes series due to testing positive as Covid-19 closes in on the series.

The Ashes series match referee David Boon has tested positive for COVID-19, Cricket Australia has confirmed.

Boon will now miss the fourth Test, starting on January 5, but is expected to return to take charge of the fifth Test nine days later.

The official is fully vaccinated – including a booster shot – and is asymptomatic. He will quarantine in Melbourne for 10 days before travelling to Hobart, where the final Test is set to be held.

Steve Bernard will serve as the referee in Boon's absence.

Boon is not the only person to miss out on the fourth Test, with England coach Chris Silverwood finding himself in the same position after a close contact contracted coronavirus.

There were four positive COVID-19 cases in the England camp on the second day of the third Test, but none of the players were affected.

Australia have already secured the Ashes, having won each of the first three Tests comfortably to move into an unassailable 3-0 series lead.

England coach Chris Silverwood will miss the fourth Ashes Test after a family member of the touring party tested positive for coronavirus.

Silverwood's position has come under question after England's dismal form in Australia, with the hosts having already retained the urn by racing into a 3-0 series lead.

Defeats in Brisbane and Adelaide were followed by a capitulation in Melbourne this week, with the third Test not even lasting three days.

Silverwood will be unable to be in attendance for the fourth match of the Tour in Sydney, as England desperately search for a result in order to avoid a whitewash.

A family member who travelled to Australia has tested positive for COVID-19 in the latest round of PCR tests administered to the touring party, the England and Wales Cricket Board (ECB) confirmed.

Silverwood will therefore have to isolate for 10 days, along with his family, in Melbourne. Another round of PCR tests will take place on Thursday.

The fourth Test is due to start at Sydney Cricket Ground on January 5, with the series finishing in Hobart after coronavirus regulations in Western Australia meant Perth was unable to host the final match.

Chris Woakes has given his support to Joe Root amid growing calls for England's star batsman to step down as captain following a chastening Ashes defeat in Australia.

The hosts took an unassailable 3-0 lead in the series after winning by an innings and 14 runs in the third Test at the MCG on Tuesday, skittling England for just 68 in their second innings, after which Root said it was "too soon to look at things."

The 30-year-old has been England's Test captain since 2017 after taking over from Sir Alastair Cook, and will lead his side out for a record 60th time in the fourth Test in Sydney, overtaking Cook's previous record of 59.

Speaking to BBC Sport, Woakes expressed his backing for Root, saying: "Joe is a great cricketer with a great cricket brain. Hopefully he can continue [as captain].

"We haven't been able to bat well around him. You'd expect us to probably put in a lot stronger performances than we have.

"I'm sure Joe will have many more years like he's already had and hopefully we can bat better around him."

England have averaged just 187.5 with the bat in six innings, failing to score more than 300 in any of the first three Tests down under.

Root has scored 1,708 runs in 2021, which equates to 26 per cent of his team's overall total, the highest proportion of any player for their respective team in Test cricket.

When asked if Root still has the backing of the team, Woakes said: "Absolutely."

The Warwickshire all-rounder was left out of the team for the third Test having taken a combined 3-228 with the ball in the first two Tests, although his batting average of 26.25 is England's third highest of the series behind only Root (42.16) and Dawid Malan (33.66).

The future of Chris Silverwood has also been called into question with the former England bowler winning just one of his last 12 Tests as coach.

"It's hard for us to focus on people," Woakes added when asked about Silverwood's position. "Who am I to talk about people's futures other than my own?"

Veteran Australian opener David Warner has set his sights on one last crack at the Ashes on English soil in 2023 as he looks to bury his demons from 2019.

The 35-year-old left-handed batsman has defied his age with the third most runs in this Ashes series after being Player of the Series as Australia lifted last month's T20 World Cup.

Warner was part of losing Australian touring Ashes parties in 2013 and 2015 and was tormented by Stuart Broad in 2019 when he was dismissed by the seamer seven times in 10 knocks, managing only 95 runs across the series which finished 2-2 with the visitors retaining the urn.

"James Anderson sets the benchmark for older guys these days, we look up to him getting on in our days," Warner told reporters.

"Winning the Ashes here was obviously a big one. We still haven't beaten India in India, that would be nice to do.

"And England away, we had a drawn series but hopefully if I manage to get that opportunity, I might think about going back."

The 89-Test veteran has scored 7,551 runs with 24 centuries but battled during the 2019 Ashes in England.

"In terms of 2019, it was obviously in England so he [Broad] was able to get the ball to come back into us and away from us," Warner said.

"For me it was one of those tours where I didn’t back my game plan and I went too defensive, and I didn’t attack. That was my fault, and he bowled really well.

"Out here, they have obviously picked Ollie Robinson for a reason ... he’s averaging 21 with the ball, he’s had some success in England, he bowls a good line and length. I wouldn’t say I was surprised, they’ve done it before in Australia.

"They haven’t played both of them [Broad and James Anderson] too often here – you might see him [Broad] play next game, and maybe Jimmy misses it. I can’t worry what they’re doing, but from our perspective I think it’s great he [Broad] is not playing."

Warner also backed under-pressure opening partner Marcus Harris who scored a game-high 76 in the third Test at the MCG after managing only 38 runs in his previous four innings.

“His courage to keep fighting and working ways out to score runs when bowlers are bowling good lines and lengths, he fought it out really well and I’m really pleased for him," Warner said.

Chris Silverwood believes England can take "positives" out of a humiliating MCG thrashing that ensured Australia retained the Ashes less than halfway through the series.

Scott Boland claimed astonishing figures of 6-7 as the tourists capitulated to 68 all out in the morning session on day three, suffering a chastening innings-and-14 run defeat.

England needed a victory to have any chance of regaining the urn, but suffered a third hammering of what has been a painful series for Joe Root's side.

James Anderson had given them hope by taking 4-33 as were Australia bowled out for 267 on day two, but their batting frailties were exposed yet again on Tuesday.

Yet head coach Silverwood says it is not all doom and gloom for England and believes he still has the players' backing.

Asked if the players are stilt responding to him as head coach, Silverwood told BT Sport: "I think they are.

"We had a good honest chat after the last game [the defeat at the Adelaide Oval]. We just have to put performances together and start pushing back.

"It is disappointing for us all and the lads will be feeling that in the dressing room.

"But I have to give credit to Australia, particularly Scott Boland on debut and Pat Cummins and Mitchell Starc for their opening spell last night.

"We had a good honest chat after the last Test, we just have to couple those performances together and find a way of pushing back against this bowling attack and scoring runs.

"Yesterday we had a little bit of disruption in the morning [a positive COVID-19 test in the team's family group] and I think the way the guys applied themselves on the field and the way the bowling attack rallied and got us back into this game was a credit to them.

"The way we caught in the last innings was good as well and I think there are positives coming out of this."

Silverwood believes England can salvage some pride in the remainder of a series that was over so soon after it started.

"We want to take something away from this series and we want to come back and compete in the last two Test matches," he added.

"We do have some world-class players and some youngsters as well who are learning on the job constantly. What we have to do is try and give them some confidence, we know they have ability and we do back them.

"We have to give them the opportunity to come out and show what they can do in the last two Tests."

Boland's figures were the best innings figures by any Australian on Test debut in Australia since Albert Trott took 8-43 against England at the Adelaide Oval in January 1895. 

Joe Root has refused to be drawn into the discussion around the state of English cricket despite Australia retaining the Ashes in record time and insists the series is not over.

England were humbled by an innings and 14 runs at the MCG on Tuesday as Australia claimed a series-clinching victory for an unassailable 3-0 Ashes lead.

Australia will now chase a 5-0 whitewash over England who were ripped apart inside an hour on the third day, bowled out for a meagre 68 which marked the nation's ninth-lowest Ashes score.

Despite the apparent gulf between the two sides and the disastrous nature of the MCG defeat, Root remained upbeat about achieving something out of the series ahead of Tests in Sydney and Hobart.

The situation has led to discussion around England's Test team and whether the County system is preparing players appropriately to compete at the elite level but Root would not be drawn on that.

"The series isn’t over yet," Root said at the post-game news conference. "We've got two very big games. It'd be wrong to look past that.

"As a player you talk about the next hour or the next session or the every next ball and managing that to be the best of your abilities, that applies to me as captain of this team.

"We have to make sure we come away from this tour with some better performances and a win or two."

Root added: "We need to put some pride back in to the badge. We need to give people back home something to celebrate and look fondly back on from this tour.

"It's bitterly disappointing to be 3-0 down but with two matches to go we have to make sure we come away with a couple of wins."

Root refused to use England's internal COVID-19 issues as an excuse for their ordinary third day display as they lost their remaining six wickets for 37 runs in 15.4 overs after resuming at 31-4.

The England skipper added that he felt his side had fought back on the second day with the ball, bowling Australia out for 267 to trail by 82 runs, but were unable to sustain their fight once again.

"I actually thought the way we went about our cricket on the field was excellent," Root told Fox Sports. "We put them under pressure and got ourselves in a position where we were very much in this Test match.

"We need to be more like that more frequently throughout the last two games."

He continued: "We've just got to do things for longer. There's been small pockets but nowhere near long enough to get into a Test match.

"We know the areas we need to improve on. We need to stay strong and make sure we use the next two Test matches as a real opportunity to take something away from this tour."

Debutant Scott Boland was "speechless" after his remarkable 7-6 spell locked in Australia's Ashes series victory over England with an emphatic win at the MCG.

Australia retained the Ashes by winning the third Test in Melbourne by an innings and 14 runs with right-arm fast bowler Boland making history in an astonishing spell.

Boland claimed four wickets in 11 balls on the third day, dismantling England's line-up as they were skittled for 68.

Australia clinched victory inside 81 minutes on the third day led by Boland's heroics, winning the game inside two days and one session.

"I'm speechless," Boland told Fox Sports after the game. "Coming in today I thought we had a pretty good chance of winning but never thought it'd be over before midday."

Boland, 32, had played 80 first-class matches prior to his Test debut, with his previous best-ever figures being 31-7.

"That's my best-ever figures," Boland said. "I got a couple of seven-fors in first-class cricket but nothing happened that quickly."

Boland, who was named Player of the Match, was fiercely supported by his home crowd, receiving wild applause every time he returned to the deep after each bowling over late on the second day and early on the third.

"They were amazing," he added. "They supported me so much from day one. Going down there just gives you a real big buzz."

Australia skipper Pat Cummins said Boland's success, having stepped up with Jhye Richardson, Michael Neser and Josh Hazlewood unavailable due to soreness or injuries, was a great sign for the hosts.

"It's a great sign for the health of Australian cricket we've got so many boys to pick from," Cummins said.

"Scotty came in, we were confident he'd do well, not quite this well, but we know whoever steps in is going to do a great job."

England only lasted 15.4 overs on the third day, with Australia retaining the Ashes within 13 days of cricket this series.

Australia lead all the key statistics, with the top four batting averages (Travis Head (62.0), David Warner (60.0), Mitchell Starc (58.5) and Marnus Labuschagne (57.25)) and top three leading wicket-takers (Starc (14), Nathan Lyon (12) and Cummins (10)) emphasising their dominance.

"I think we've been relentless with bat and ball when we've had to be," Cummins added. "The bowlers turned up and owned that good area around the top of off stump.

"The batters have really earned their runs. Some partnerships, Marnus [Labuschagne] and Davey [Warner] have earned the right to bat long, they've left well.

"When opportunities presented they've been brave and taken on the game. All round everyone has contributed."

Australia can claim a 5-0 whitewash with victories in Sydney and Hobart in the remaining two Test matches.

"I think any Ashes series is where you try to make a mark in your Test career," Cummins said. "Back to last series 4-0 and the one before that was 5-0, that goes down in history.

"We've got a chance to start cementing our identity and [it] can be the start for the next few years."

Victorian debutant Scott Boland produced the spell of a lifetime as Australia secured an Ashes series victory with an emphatic triumph over England in the third Test at the MCG on Tuesday.

England were skittled for a feeble 68 as Australia clinched an unassailable 3-0 series lead with victory by an innings and 14 runs inside two days and one session.

Player of the Match Boland was the story of the third day, claiming four wickets in 11 deliveries including England skipper Joe Root to finish with remarkable second-innings figures of 7-6 from four overs.

Root offered the only resistance with 28, after the visitors resumed at 31-4 but wilted against a hungry Australian attack.

Mitchell Starc (29-3) got the first breakthrough of Ben Stokes bowled for 11, before Boland took over as England lost their final five wickets for eight runs.

Boland first trapped Jonny Bairstow lbw for 5, despite a review, after he was dropped at gully by Cameron Green.

The debutant proceeded to claim the key wicket of Root caught by David Warner at first slip, before dismissing Mark Wood and Ollie Robinson for ducks.

Green claimed the final wicket to secure the series victory, clean bowling Jimmy Anderson to bowl England out for 68, their ninth lowest total in Ashes history.

England lasted only 15.4 overs on the third day, with the game being the shortest completed Test match hosted by Australia in 70 years, lasting 1084 balls.

The all-clear was given for day three of the Boxing Day Ashes Test to start on time after Australia and England players all tested negative for coronavirus.

There had been a scare ahead of the second day of the third Test in Melbourne when a member of the tourists' family group returned a positive COVID-19 result.

The England players and management were forced to remain at their hotel while they awaited their test results, before being given the green light to travel to the ground, with play starting half an hour later than scheduled.

Both sets of players took PCR tests after the second day of play and Cricket Australia on Tuesday confirmed all tested negative, meaning there were no delays for the third day.

The England team's support staff and the family members who tested positive on Monday – reportedly six people in total – are in isolation.

Australia were well on course to retain the urn after reducing Joe Root's side to 31-4 in their second innings after two days of play, with England trailing by 51 runs and 2-0 down in the series.

Marcus Harris said "it's about trusting what I do" after going some way to silencing his doubters on day two of the third Ashes Test against England.

The opening batsman went into the contest at the MCG with a best effort of 23 from four innings, but top scored with 76 – the only Australian to make more than 40 in the first innings.

It proved a particularly good knock in the context of a day that saw Australia restricted to 267 having bowled England out for 185 on day one, before dominating the final hour to have the tourists 31-4 and still 51 runs in arrears.

Harris was thrilled to play his part on his home ground and prove a few people wrong in the process.

"It was good to spend a bit of time in the middle today. I had a bit of a battle in the first couple of Tests but it was good to be home and play on a familiar wicket," he told ABC Radio.

"There's a lot of media around but the support I've had from within and my close circle of people has been unbelievable. It's about trusting what I do."

James Anderson had starred with the ball for England, taking 4-33 to give the visitors an opportunity to get back into the game.

But Mitchell Starc (2-11) and Scott Boland (2-1) combined to have Zak Crawley (5), Dawid Malan (0), Haseeb Hameed (7) and nightwatchman Jack Leach (0) dismissed in a devastating final hour, much to the delight of the Melbourne crowd.

Harris added: "The way the wicket is, the amount of grass, there's always something in it for the bowlers.

"Jimmy Anderson bowled unbelievably, as did our bowlers in the end."

James Anderson rued England's disappointing final hour after the tourists had worked hard to fight their way back into the third Ashes Test against Australia on day two.

Having been bowled on for 185, England's star paceman Anderson led the way with 4-33 to restrict Australia to 267 all out and a first-innings lead of 82 at the MCG.

But a woeful last hour amid familiar failings with the bat saw England close on 31-4, still trailing by 51 runs as Australia moved ever closer to sealing the series.

"It's obviously a disappointing finish to the day, I thought we bowled well through the day to keep the pressure on Australia," England's all-time leading wicket taker Anderson told BT Sport.

"It wasn't easy to bowl them out for less than 300 on that wicket but it was a good effort to do so.

"It was a difficult 12 overs, good spell from Mitchell Starc and Pat Cummins, they're world-class bowlers so you expect that. It was disappointing to lose four wickets in those 12 overs."

England looked set to enjoy their best day of a poor series so far until Starc (2-11) and home favourite Scott Boland (2-1) combined to have Zak Crawley (5), Dawid Malan (0), Haseeb Hameed (7) and nightwatchman Jack Leach (0) dismissed, much to the delight of the Melbourne crowd.

Anderson, though, insists there is plenty of unity within England's camp.

"It's been a frustrating tour so far full stop. We are working hard and trying to put things right and trying to put in better performances," he added.

"I thought we did that with the ball, we hit our areas with the ball but it was a frustrating end to the day.

"We are together as a group. We have a really good group of guys. We know how hard the batters are working and as bowlers we are doing the same. 

"The cohesion is definitely there it's just frustrating we are not putting the two things together at the same time."

Australia took four late wickets amid a devastating spell with the ball to grab a stronghold on their way to sealing the Ashes after England had fought back on day two of the third Test at the MCG.

Mitchell Starc claimed the scalps of Zak Crawley and Dawid Malan in successive balls before Victorian debutant Scott Boland had Haseeb Hameed caught behind and bowled Jack Leach to leave the visitors reeling.

England were 31-4 at stumps, trailing by 51 runs as Australia, who lead the series 2-0, look to clinch the Ashes in Melbourne. Joe Root (12*) and Ben Stokes (2*) will resume at the crease on day three.

The visitors had rallied to keep the Boxing Day Test alive, having dismissed Australia for 267 led by veteran James Anderson with 4-33.

All this after drama forced the resumption of play to be delayed after a coronavirus scare within the England camp, before all the players were cleared for an 11am local start.

Australia had resumed at 61-1 after England were all out for 185 on the first day. Marcus Harris resumed at the crease and top scored with 76 on his home deck.

England had made good inroads into the Australia batting order at 110-4, dismissing number one Test batsman Marnus Labuschagne for 1 and vice-captain Steve Smith for 16 from Chris Wood (71-2) and Anderson respectively.

Harris was the only Australian to score more than 40, with Travis Head (27) getting a start before falling to Ollie Robinson (64-2), who had a hamstring scare but played on.

England appeared set for a nominal first-innings deficit before a late cameo from Starc (24*) and captain Pat Cummins (21) opened up an 82-run lead.

However, Australia turned the game in a stunning final 45 minutes with Cummins almost having Crawley caught behind for a duck when Alex Carey botched a chance, before the English opener went in the next over to Starc (11-2).

Starc trapped Malan lbw next ball despite a review, before Boland was introduced to the attack, having Hameed caught by Carey before clean bowling Leach two balls later.

Starc misses rare Boxing Day hat-trick

Starc almost claimed the first Boxing Day Test Ashes hat-trick since Shane Warne in 1994 when he dismissed Crawley and Malan in successive deliveries. England skipper Root survived a close call on the hat-trick ball which had the MCG crowd on their feet as it whizzed past the bat.

Local hero fires up crowd

Local debutant Boland only managed one wicket in the first innings but received great support from his home crowd during his brief batting innings before a double strike with his only over after being thrown the ball late in the day.

England suffered a coronavirus scare ahead of day two of the third Ashes Test against Australia at the MCG.

The players and management were forced to remain at their hotel after a positive COVID-19 test was recorded within the team's family group.

Players and staff had to await the results of their own coronavirus tests before eventually being given the all-clear to head to the stadium.

England, who trail the series 2-0, were bowled out for 185 on day one after Australia won the toss and put the tourists in.

Australia will resume on 61-1 after James Anderson accounted for David Warner (38) before the close of play on day one.

Pat Cummins need only to avoid defeat in Melbourne to retain the Ashes after one-sided victories in Brisbane and Adelaide.

England have made sweeping changes ahead of the Ashes Boxing Day Test with Rory Burns, Ollie Pope, Stuart Broad and Chris Woakes all omitted.

Batsmen Zac Crawley and Jonny Bairstow earn their first opportunities during this Ashes series while paceman Mark Wood and spinner Jack Leach have been recalled.

England trail 2-0 in the Ashes after heavy defeats in Brisbane and Adelaide and will look to keep the series alive at the MCG starting on Sunday.

Opening batsman Burns has been left out after managing only 51 runs at 12.75 along with Ollie Pope with 48 runs at 12 in the first two Tests.

Broad and Woakes make way as England look to add variety to their attack which has allowed Australia to score more than 400 runs in the first innings of both Test matches.

England vice-captain Jos Buttler told reporters on Saturday: "I'd say the reaction is just an honest one from the group. We've had some honest conversations.

"When you come and play Australia we need to be at your best. We're honest with ourselves that we haven’t been there yet. We have to find that very quickly."