Ash Barty produced an impressive comeback to defeat Coco Gauff in her first singles match since the US Open.

World number one Barty moved into the quarter-finals of the Adelaide International with a battling 4-6 7-5 6-1 triumph.

The home hope, who is favourite to win the Australian Open when it starts later this month, was a set and a break down against the American wonderkid before ultimately progressing in two hours and 12 minutes.

Exhausted after a six-month road trip that included Wimbledon glory last year, Barty took a break from the WTA Tour after her third-round exit at Flushing Meadows on September 5.

Her return came in a marquee matchup at the WTA 500 event which did not disappoint, as Barty battled to win 11 of the last 13 games and prevail.

The victor stemmed the early errors she was making on the forehand side, with Gauff paying the price for only converting three of her 15 break-point opportunities. 

It was only the second meeting between Barty and Gauff, with the Australian having to retire with an arm injury while leading their first encounter in Rome last year.

"I felt like I played a pretty good quality match considering it was my first match in a few months," said Barty.

"In the first set I was able to create opportunities but just was a little bit slack on the execution, rusty in the sense of stringing quality points together.

"Midway through the second set I was able to find my rhythm a little bit better on serve and just continued to be aggressive on my forehand. I just found execution a little bit more.

"Coco played great and forced me to hit a lot of balls. I felt I got better and better as the match went on. It was nice to get some court time."

An intriguing last-eight tie lies in wait for Barty. She will either play former Australian Open champion Sofia Kenin or compatriot Ajla Tomljanovic.

And there was more good news for Barty as two of her main rivals for glory were eliminated.

Second seed Aryna Sabalenka was surprisingly beaten as Kaja Juvan, the world number 100, prevailed 7-6 (8-6) 6-1.

Maria Sakkari, the third seed, also crashed out, beaten in three sets by Shelby Rogers, the player who knocked Barty out of the US Open the last time the Australian was on court.

There are two other tournaments taking place this week, both at WTA 250 level.

At Melbourne Summer Set 1, second seed Simona Halep joined Naomi Osaka in round two with a routine 6-4 6-2 win over Destanee Aiava.

The field is not as strong at Melbourne Summer Set 2, where the highest seed remaining, Daria Kasatkina, progressed after opponent Anna Kalinskaya, having already lost the first set, withdrew through injury.

Novak Djokovic will be on the "next plane home" if he fails to prove he merits a medical exemption to play in the Australian Open.

Tournament organisers have faced a backlash after it was announced this week that Djokovic has been granted a medical exemption to play in the first grand slam of the year.

The Serbian has refused to state whether he has been vaccinated, but protocols in Australia require proof that competitors and staff have been jabbed or have a medical exemption to compete at Melbourne Park.

Tournament director Craig Tiley insisted that the 20-time major champion had not been given a "special favour" to play in the tournament.

Australian Prime Minister Scott Morrison on Wednesday stated that Djokovic will not defend his title if he fails to show that he is exempt.

He told reporters: "We await his presentation and what evidence he provides us to support that.

"If that evidence is insufficient, then he won't be treated any different to anyone else and he'll be on the next plane home. There should be no special rules for Novak Djokovic at all. None whatsoever."

Tiley told The Today Show on Tuesday: "There's been no special favour. There's been no special opportunity granted to Novak.

"As an organisation and as a sport, we've done what everyone else does and would do if they wanted to come to Australia and under certain conditions.

"And we have abided by those conditions and I know Australia's had the most comprehensive response to COVID of any nation in the world. And our governments have done everything they humanly possibly can to keep us safe.

"It's ultimately the decision of the medical experts and we follow that accordingly. In this case, Novak made that application.

"And like others, there's been 26 athletes and their primary support staff that have made applications and a handful of those have been granted by the panel.

"The conditions in which any tennis player comes in, no matter who they are, are conditions that have been put on tennis and put on anyone coming into Australia by the Australian government."

The Australian Open begins on January 17.

Jimmy Butler has been ruled out for the Miami Heat ahead of their game at the Portland Trail Blazers on Wednesday.

Five-time All Star Butler had to be helped from the court after suffering an ankle injury during Monday's loss to the Golden State Warriors.

And the Heat will have to do without the swingman, who is averaging 23.2 points, 5.9 rebounds, 5.5 assists this season, as they look to avoid a third straight NBA defeat.

Butler has already missed 15 games so far in 2021-22, some due to issues with the same right ankle, while he also had a tailbone injury.

The team did not provide any further details on his status other than ruling him out of the game against the Trail Blazers.

Miami had won five games in a row prior to consecutive road losses against the Sacramento Kings and the Warriors, who won 115-108 with Butler forced off towards the end of the third quarter.

The team sit fourth in the Eastern Conference with a 23-15 record, having made it to the NBA Finals last season.

Miami were already due to be without Bam Adebayo and Duncan Robinson against Portland (14-22).

The EFL Cup semi-final tie between Liverpool and Arsenal has been thrown into further doubt after Pep Lijnders returned a suspected positive COVID-19 test.

Liverpool assistant Lijnders was poised to take charge of the Reds in Thursday's first leg at the Emirates Stadium with manager Jurgen Klopp still isolating after his own positive test.

But Lijnders will now join the German in isolation and the news conference he was poised to lead on Wednesday has been cancelled.

The update comes a day after Liverpool formally requested the postponement of the first leg after confirming an "escalating number" of suspected COVID-19 cases.

Lijnders' result came in after that application, which Liverpool are still awaiting a response to. 

"Liverpool Football Club can confirm Pepijn Lijnders has returned a suspected positive test for COVID-19, further impacting the club's preparations for Thursday's Carabao Cup tie with Arsenal," read a statement from the club.

"The assistant manager had been due to handle pre-match media duties at the AXA Training Centre in place of Jürgen Klopp, who is continuing to isolate having tested positive for the virus last week.

"However, Lijnders recorded a positive test late on Tuesday evening, meaning he has now also gone into isolation.

"The 38-year-old took interim charge of Liverpool for the weekend draw at Chelsea in the absence of Klopp and had been set to continue at the helm at Emirates Stadium on Thursday.

"Lijnders' test result comes in addition to a number of suspected positive cases among players and football staff recorded earlier on Tuesday, which forced the cancellation of the day's scheduled training session.

"As a result of the outbreak and the suspension of preparations, as well as other illnesses and injuries recorded within the squad, the club submitted an application to the EFL for the postponement of Thursday's tie with Arsenal, with the news of Lijnders' positive result coming after the request was lodged.

"The outcome of this application is still pending."

If Thomas Tuchel is after any advice on how to deal with the Romelu Lukaku issue, the Chelsea head coach could do worse than to have a brief word with the man he will come face-to-face with on Wednesday.

Under now-Tottenham boss Antonio Conte across two seasons with Inter, Lukaku enjoyed the best form of his career, scoring and assisting a combined 81 goals in 95 appearances.

Lukaku has not been as prolific since returning to Stamford Bridge in August, finding the net seven times in 18 games, and already his future at Chelsea has been called into question following an explosive interview in the Italian press that was published last week.

The Belgium international was subsequently dropped for Chelsea's crucial clash with Liverpool on Sunday but is in line return for the EFL Cup semi-final first leg with Spurs after holding clear-the-air talks with his manager, meaning a possible reunion with Conte.

Here, Stats Perform looks at how Conte got Lukaku out of the "deep hole" he found himself in at Manchester United, as the striker himself put it, and explores how Tuchel can go about getting the most out of Chelsea's all-time record purchase.

ROM AMONG EUROPE'S ELITE

As well as declaring an unhappiness with his role at Chelsea and expressing a desire to return to Inter as part of his 30-minute chat with Sky Sport Italia, Lukaku also opened up on the "hurt" he felt when Conte departed San Siro.

That is no surprise given the Belgian's form between arriving at Inter in August 2019 and departing two years later. 

The 47 Serie A goals scored by Lukaku in 72 games under Conte is his best return under any of the 11 managers he has played for at club level, followed by the 43 netted in 103 Premier League games when working with now-national team coach Roberto Martinez at Everton.

That includes a return of 24 goals in 2020-21 alone, on top of 11 assists, as he became the first player to score 20-plus goals and set up 10 or more in a single Serie A season since Opta started to record such data in 2004-05.

Indeed, only Cristiano Ronaldo (83), Kylian Mbappe (97), Lionel Messi (106) and Robert Lewandowski (121) were directly involved in more goals in all competitions among players from Europe's top five leagues than Lukaku's 81 across the 2019-20 and 2020-21 seasons.

FLOPPED IN FAVOURED FORMATION

That impressive form helped Inter end their 11-year wait for Scudetto success last time out, a year on from falling just short in the Europa League with defeat in the final, but Lukaku was not alone in inspiring the Nerazzurri to glory.

Alongside him was Lautaro Martinez, who was very much the perfect foil in Conte's preferred 3-5-2 formation, which the Italian used 31 times in 38 league matches last season.

It is a formation Tuchel has used on only two occasions in the Premier League this term – in September's 1-0 home defeat to Manchester City and the 1-0 victory at Brentford three weeks later. 

Lukaku started both games alongside Timo Werner and Chelsea's tally of five shots against City and five against Brentford are the fewest the Blues have managed in any league game this term – Lukaku responsible for just one of those – as were the four and two chances created respectively.

While City's quality and dominance of the ball must be factored in, Lukaku's minimal involvement against Brentford was surprising – and surely no coincidence.

That west London derby blank came in the midst of a 10-game run without a goal for Lukaku, not helped by niggling injuries and a COVID lay-off, which he has since put an end to with three goals in four matches.

Chelsea's formation in those three most recent games Lukaku has scored in, incidentally, came with three attackers spread across the frontline. And there was one other common denominator, too: Mason Mount being on the field.

MOUNT TO PLAY THE MARTINEZ ROLE?

Mount assisted Lukaku's most recent goal in a 1-1 draw against Brighton and Hove Albion from a corner and the pair have combined to create nine chances in total for one another in the league this term, making it easily Chelsea's most dangerous partnership.

No Chelsea player has combined more regularly with Lukaku than Mount, with the pair linking up 10.06 times per 90 minutes so far this season. While that may not appear a huge amount on the face of it, next on that list is Mateo Kovacic with 6.45 combined passes between himself and Lukaku per 90.

However, Mount still has some way to go if he is to match the 54 combined chances created for each other in Serie A by Lukaku and Martinez in their two seasons used in tandem at Inter, which equated to nine assists.

Lukaku's relationship with Mount does provide some promise, though, as does the Anderlecht academy product's goalscoring performances in his most recent two outings prior to being dropped against Liverpool, showing Chelsea do not necessarily have to replicate Inter's system to help their main man thrive.

TUCHEL WILL NOT SHIFT

Lukaku is averaging fewer passes, overall touches and touches in the opposition box this season compared to last, while also shooting less frequently, dribbling less and creating fewer chances for others.

Yet instead of attempting to find the perfect formula and personnel for Lukaku, Tuchel will not shift from his own way of thinking.

"We cannot just play like Inter in the hope that will bring the most out of Lukaku. The system they played not only suited Romelu but also Lautaro Martinez and others. If you don't have five players you can't play five defenders," Tuchel said on the eve of the Tottenham tie.

"It works both ways. It is more about principles of how we play. I feel he is more impatient than anything else. He wants to be involved more, wants more big chances. 

"Like with every transfer, you have to accept there is a change of environment, culture, team-mates, playing style, belief. He's not the first player to take time, but even while doing it he was scoring goals."

And maybe Tuchel has a point. After all, for all the talk of Lukaku's struggles and unhappiness, he is scoring at an almost identical rate to Cristiano Ronaldo (0.54 goals per 90 minutes compared to 0.56), and remains one of Europe's most prolific strikers of the past decade.

Now back from injury and a team exile brought on by his own actions, only Lukaku can ensure he avoids falling down another deep hole that he may this time be unable to escape.

England struck twice late on a rain-affected opening day of the fourth Ashes Test at the SCG to get back into the contest on Wednesday.

Australia finished the first day on 126-3 with Steve Smith (6 not out) and Marnus Labuschagne (4 not out) at the crease after captain Pat Cummins won the delayed coin toss and elected to bat.

The hosts, who lead the series 3-0, had been firmly in control at 111-1 in the final session before veteran Jimmy Anderson (24-1 from 13 overs) and Mark Wood (31-1 from 10 overs) struck to dismiss opener Marcus Harris (38) and Test number one batsman Labuschagne (28) respectively.

Stuart Broad, back in the England side at the expense of Ollie Robinson, claimed the scalp of opener David Warner for 30 caught by Zak Crawley.

The opening session had been stop-start with rain delays seeing Australia go into lunch at 30-0, before adding another 26 runs until Broad found an edge from regular scalp Warner.

Rain fell shortly after Warner's dismissal leading to tea being taken after only 21.4 overs of play, but England got a crucial double strike in the final session before the weather intervened again.

Harris had been patient across more than three hours at the crease until Anderson drew an edge which Joe Root claimed at second slip.

England skipper Root introduced Mark Wood into the attack in the next over and dismissed Labuschagne caught behind by Jos Buttler.

Broad has the wood on Warner

Broad resumed his domination of Warner, dismissing him for the 13th time in Test cricket when he struck in the second session.

The right-arm fast bowler dismissed Warner seven times in the space of 104 balls during the 2019 Ashes in England, yet has been left out for two Tests in this series.

Sydney's rain woes

Only 46.5 overs were bowled on the first day at the SCG, which has been plagued by rain at recent Test matches at the venue.

In fact, Sydney has lost 26 days of Test cricket due to rain since 1877, which is significantly the most of any Australia venue and, while there was play, it was a frustrating opening day.

Los Angeles Lakers head coach Frank Vogel says LeBron James scoring 14 final-quarter points and leading the side to victory over the Sacramento Kings is "just who he is".

James had shot six-of-17 from the field for the game, before stepping up in the fourth quarter to lead the Lakers past the Kings 122-114 on Tuesday.

The four-time MVP finished with 31 points, sinking two three-pointers in a row with under five minutes to go, turning around his shooting struggles from earlier in the game.

"You always know that's a possibility," Vogel said at the post-game news conference. "If he's not having a good shooting night, like anybody, you coach him.

"You have to coach him like everybody else but you never lose belief that he's going to do what he did in the fourth quarter. That's just who he is.

"If anything, I think the tweaks we made tonight were about what he was doing on the defensive side.

"He was exerting energy trying to double down. We had to pull back some of that."

The victory means the Lakers have won three in a row after a recent five-game skid, improving to 20-19.

James has averaged 28.5 points, 7.5 rebounds and 6.6 assists per game this season.

LeBron James powered the Los Angeles Lakers to a hard-fought 122-144 win over the Sacramento Kings with a last-quarter barrage on Tuesday.

James finished with 31 points including 14 in the fourth quarter along with five rebounds and five assists for the game to help the Lakers improve to 20-19.

With the Lakers trailing 102-101 with less than five minutes to go, the four-time MVP hit back-to-back three-pointers to claim the ascendancy.

Malik Monk contributed 24 points for the Lakers, while Russell Westbrook had 19 points and seven rebounds.

De'Aaron Fox scored 30 points with three rebounds and six assists for the Kings who move to 16-23.

Paul and Booker shine for Suns

Chris Paul provided 15 assists alongside his 11 points as the west's second seeds, the Phoenix Suns, defeated the New Orleans Pelicans 123-110. Devin Booker scored 33 points for the Suns with nine rebounds and four assists, while Jonas Valanciunas had 25 points with 16 rebounds for the Pels.

The Memphis Grizzlies secured their sixth straight win with a 110-106 victory over the Cleveland Cavaliers led by Ja Morant with 26 points, five rebounds and six assists. Darius Garland (27 points and 10 assists) and Kevin Love (18 points and 10 rebounds) were good for the Cavs.

Sabonis struggles from stripe

Domantas Sabonis struggled from the stripe making five-of-12 free-throws while he was bossed by Julius Randle as the Indiana Pacers were beaten 104-94 by the New York Knicks. Sabonis only managed 15 points with eight rebounds, while Randle scored 30 points with 16 rebounds. The Pacers have lost five in a row.

Pittsburgh Steelers head coach Mike Tomlin refused to get caught up in his own record-breaking history after sealing 15 consecutive seasons without a losing record.

The Steelers beat the Cleveland Browns 26-14 on Monday to keep alive their playoffs hopes with a 8-7-1 record with one game left.

The victory also meant Tomlin will avoid a losing season for the 15th consecutive year, which exceeds Marty Schottenheimer's streak from 1984 to 1997 to begin an NFL career.

"Not as I sit here today, and I say that humbly," Tomlin told reporters when asked if the record meant anything to him. "Our agenda, this year, is to get into the single-elimination tournament and then pit our skills against others in that single-elimination tournament in an effort to win the world championship.

"That's our mentality every year and so with that mentality, it's just certain hardware that you expect to pick up along the way. If you don't, you'd be seriously disappointed. That's just an expectation that we have here in Pittsburgh."

Pittsburgh are second in the AFC North with the Cincinnati Benglas having seal the divisional title on Sunday.

Tomlin's Steelers face divisional rivals the Baltimore Ravens in the final regular season game on Sunday as both chase a victory to be in contention for an AFC wild card berth.

Tomlin remains the youngest head coach to win the Super Bowl, when he led the Steelers to the title in 2009 at 36-years-old.

Philadelphia Eagles quarterback Jalen Hurts says Sunday's railing collapse at FedEx Field "could have been so much worse" and wants changes made.

Hurts was exiting the field after Sunday's 20-16 win at the Washington Football Team when railing on the side of the tunnel collapsed with fans falling and spilling on to the ground.

The Eagles QB narrowly avoided being crushed by the fall and assisted fans to their feet and posed for pictures with them but insisted it cannot happen again.

"I tried to handle the situation with a lot of poise and show compassion for the people that fell down, really, but I know it could have been so much worse," Hurts said during a news conference.

"It kind of didn't hit me until after the fact, having some time to reflect on it and think about it. I just wanted to see what could be done to make sure it doesn't happen again. That's all I really care about."

Hurts has penned a letter to the Washington Football Team seeking clarification on what safeguards can be put in place to ensure it never happens again.

"What follow-up action is being considered in response to the near-tragic incident that took place at FedEx Field on January 2, 2022," Hurts wrote.

"Through the initial shock, my first reaction was to assist those involved. However, while I displayed a calm composure, I understand the severity of what happened and am extremely concerned for the well-being of the fans and media.

"As a result, I would like to know what safeguards the NFL and the Washington Football Team are implementing to prevent this from ever occurring in the future.

"The resources of the NFL and team organizations ensure our safety through playing this physical sport, but what happened Sunday put both fans and players unnecessarily at risk long after the final whistle. I look forward to hearing from you on this matter."

There have been reports of minor injuries from those involved in the fall but Washington released a statement following the incident on Sunday which said: "To our knowledge, everyone involved was offered onsite medical evaluation and left the stadium of their own accord."

Novak Djokovic has not been granted any "special favour" for a medical exemption to play in the Australian Open, tournament director Craig Tiley insisted.

Djokovic announced on Tuesday that he was on his way to Melbourne for the first grand slam of 2022, a revelation that was met with a host of criticism.

The world number one has not openly addressed whether he has been vaccinated for COVID-19, but protocols in Australia require proof that competitors have been jabbed or have a medical exemption to feature at Melbourne Park.

The Serbian has been vocal in his opposition for vaccine mandates, calling for freedom across the world, and is now expected to be welcomed with a frosty reception by those in the country battling a surge in cases of the Omicron variant.

Tiley spoke on the matter, coinciding with confirmation from the Australian Open that the 34-year-old was set to compete, as he referenced the "fair and independent protocols" in granting exemptions.

The tournament director has since reiterated his defence over the decision to allow Djokovic to defend his title, and search for a record 21st singles grand slam triumph, as he insisted there had been no preferential treatment.

Tiley said on Australia's The Today Show: "There's been no special favour. There's been no special opportunity granted to Novak.

"As an organisation and as a sport, we've done what everyone else does and would do if they wanted to come to Australia and under certain conditions.

"And we have abided by those conditions and I know Australia's had the most comprehensive response to COVID of any nation in the world. And our governments have done everything they humanly possibly can to keep us safe.

"It's ultimately the decision of the medical experts and we follow that accordingly. In this case, Novak made that application.

"And like others, there's been 26 athletes and their primary support staff that have made applications and a handful of those have been granted by the panel.

"The conditions in which any tennis player comes in, no matter who they are, are conditions that have been put on tennis and put on anyone coming into Australia by the Australian government."

Roger Federer and Rafael Nadal also sit with Djokovic on 20 major crowns, but the Swiss star is already ruled out of the tournament, which starts on January 17, through injury.

Nadal could yet compete after posting pictures showing he was in Melbourne as he continues to recover from a positive COVID-19 test in recent weeks.