Chelsea head coach Thomas Tuchel has tested positive for COVID-19.

The club confirmed the news just over an hour before Saturday's FA Cup fourth-round match with Plymouth Argyle at Stamford Bridge.

Tuchel, who is self-isolating, will not fly out with the Chelsea squad for the Club World Cup in Abu Dhabi next week, although it is hoped he will be able to join them at a later date.

The rest of Chelsea's travelling group are due to depart for the United Arab Emirates after the Plymouth game.

European champions Chelsea face a semi-final on Wednesday against either AFC Champions League holders Al Hilal or 2020-21 UAE Pro League winners Al Jazira.

Manchester City boss Pep Guardiola is enthused by the signing of Argentina international forward Julian Alvarez from River Plate, describing the transfer as "a really, really good deal".

The Premier League leaders announced the signing of Alvarez on Monday, when the forward turned 22, in a deal worth a reported £14million ($18.8m).

Alvarez has signed a five-and-a-half-year deal but will stay with River on a loan that will last until at least July and could be extended.

He had been linked with a number of Europe's biggest clubs after scoring 24 goals in 46 games for River in all competitions during an impressive 2021.

That form saw him earn his first senior Argentina cap in June and he has gone on to feature a further five times for his national side.

"I saw him many times, I have the info about him and for the age, for the price, for many reasons and for the future it's a really, really good deal," said Guardiola.

"He is a guy who has a sense of goal, the quality, the movement in behind - a street player.

"The club decided OK, for that age and especially for the fact he stays under Marcelo Gallardo, one of the best managers in the world by far, he's going to develop again and again in this part of the season.

"He is so dynamic. I think when he is playing the goal is there in his mind with the way he finishes and makes the movements over five metres."

Describing what else he likes about the new signing, Guardiola added: "He has the desire, the passion and the strength without the ball.

"He is so young and you see that. He is hungry. At that age it is so nice to have. It can refresh so many things in a team when you have that.

"That is why I love to work with academy players, when they have the talent and skills, and they are good here.

"When that happens, it is so productive for the senior players that we have because they produce something new in terms of rhythm, with no complaints.

"I like to have 15 or 16 top players otherwise you can’t compete. The rest I like to have from the academy, but they have to be good, or it makes no sense.

"In pre-season he will come, he will join us and after that we'll see what happens."

Guardiola sees Alvarez playing in a central role for City when he joins up with them.

"Up front, in the middle," he said after being asked where Alvarez may fit into his line-up. "I see a player more in positions between the pockets and the striker. 

"A guy with this sense of goal has to play close to the goal."

City host Championship side Fulham in the FA Cup fourth round on Saturday.

Kyrie Irving says it is time for the struggling Brooklyn Nets to face the reality of their situation in the NBA but urged the team not to panic.

As the returning Donovan Mitchell dominated, Brooklyn went down to a heavy 125-102 loss to the Utah Jazz on Friday.

James Harden (hamstring), Kevin Durant (knee), LaMarcus Aldridge (ankle) and Joe Harris (ankle) were all again absent for a Nets team who have lost seven straight games.

The team were tipped for a championship run this season but have plummeted to sixth in the Eastern Conference ahead of Sunday's trip to Denver to face the Nuggets.

Amid the Nets' worst run of the season, Irving told ESPN: "It's really just where we are, facing reality that we are not winning ballgames right now.

"We have got to kind of get out of that hole with just one win and then start a new streak from that point. 

"[There is] no time to feel like our season is in doomsday or that we need to push the panic button at all points.

"But we have to face reality that a lot of guys, a lot of my teammates, we're still getting to know one another, how we play, what's our spots, offensive and defensive tendencies.

"And then communication - knowing that we can get on guys and guys love to be coached. 

"It's not just from the head coach or the assistants but really just from us as teammates and then trusting that we have the experience to win basketball games."

Irving, who cannot play in home games due to COVID-19 vaccination rules in New York City, insists building a winning culture takes time.

He had a poor game against the Jazz, finishing with 15 points in 31 minutes on court after going just six for 20 from the field.

"Myself alone, I can't do it," Irving said. "It's always going to be about the collective unit and how we feel good about being close as a team and then going out there and playing basketball, which is supposed to be fun. 

"But when you're losing and it's a win-first league and a win-only league - you get judged by wins and statistics and how well you put a streak together and how consistent you are. So the spot we're in is going to look like it's far worse than what it is.

"Being in this league for as long as I have been for 11 years, I've seen ups and downs, experiences.

"We have just got to trust that we have the group regardless of who's in or out of the lineup to be able to put a 48-minute game together.

"I don't feel like I'm close to where I want to be personally.

"I have mountain-high expectations for myself, but right now I feel like with our personnel, if I'm not shooting well or I'm not playing well or we don't have the same production from guys that we're used to getting it from, it's going to be a tough night. 

"Building championship habits takes time and time is not necessarily always on our side. 

"It is about staying resilient and knowing that there's another level to push to when you're tired and you have all the excuses in the world and you just continue on. You don't hold your head or anything like that."

Rookie Cam Thomas was one bright spot for the Nets, posting a career-high 30 points.

Donovan Mitchell's performance "looked like a video game" as he made a spectacular return to the court after missing eight straight games due to a concussion.

That was the view of his Utah Jazz teammate Udoka Azubuike after Mitchell made up for lost time as the Jazz, fourth in the Western Conference, outclassed the out-of-form Brooklyn Nets 125-102 on Friday.

Mitchell ended the game with 27 points in just under 22 minutes, draining six of his seven three-point attempts and adding six assists.

He set a franchise record for most points scored in under 22 minutes, while Bojan Bogdanovic was a valuable ally with 19 points and 11 rebounds, ensuring the Nets were consigned to a seventh consecutive defeat.

Azubuike found himself in disbelief at Mitchell's heroics.

"He was unbelievable," Azubuike said about Mitchell. "It looked like a video game. There was one time I had to catch myself in the moment because I was just watching him. 

"Every shot was going in. Don is a star."

For Mitchell, who has reached three straight All-Star Games, getting back to action was the most important factor after the Jazz went 2-6 in his absence.

"I was just happy to be playing basketball," he said, per ESPN. "I was joking before the game that I didn't care if the ball went in. 

"I was just happy to be out there running around, guarding, thinking the game and playing with my teammates.

"I'd rather be out there playing, but I just told someone my legs haven't felt that fresh in a long time."

With Quin Snyder in the COVID-19 health and safety protocols, it was Alex Jensen who acted as interim coach for the Jazz, with Mitchell's return making his task more straightforward.

"There's so much focus other teams have on him that it frees up other guys offensively," said Jensen.

"He's Donovan Mitchell and makes life a lot easier for everybody."

James Harden (hamstring), Kevin Durant (knee), LaMarcus Aldridge (ankle) and Joe Harris (ankle) were all again absent for a Nets team who have plummeted to sixth in the East.

The Nets' Kyrie Irving acknowledged they had come up against one of the NBA's biggest stars in Mitchell.

"We have a lot of special guys in our league," said Irving, who ended the game with 15 points after going just six for 20 from the field.

"But there are a few special guys that even separate from that group of just being special and he's one of those people." 

The Jazz host the New York Knicks on Monday in the third contest of a six-game run at home that has so far produced two victories from two.

Brooklyn, meanwhile, will be in Denver to face the Nuggets on Sunday.

Manchester United winger Jadon Sancho should be fit to face Burnley after his goal against Middlesbrough in the FA Cup.

Sancho scored his first goal at Old Trafford since his lucrative move from Borussia Dortmund seven months ago, but Championship side Boro controversially equalised through Matt Crooks on Friday.

The match then ended level at 1-1 and, after no goals in extra-time, it was the visitors who reached the fifth round in a huge upset, winning 8-7 on penalties.

United are straight back to action against Burnley in the Premier League on Tuesday, the second of a hectic seven-match run of fixtures up until February 26.

Despite being replaced by Juan Mata after appearing to have a hamstring issue against Boro, Sancho should be fit to play his part at Turf Moor.

The man who assisted his goal, Bruno Fernandes, is also set to be available as United look to bounce back.

"Jadon didn't get a knock," United boss Ralf Rangnick told MUTV. "He was just feeling tired.

"He had no injury, he was just feeling some fatigue and had some cramp so that was the reason why we decided to take him off.

"Bruno had a knock on his back but could play through the whole game.

"With Paul Pogba having been out for two and a half months, it was normal that he was substituted after 65, 70 minutes.

"Physically, I don't think we need to lift the squad. Hopefully, for Tuesday, we will have all of those players available again."

United were punished for missing a hatful of chances as they failed to win a home FA Cup match against a lower-league side for just the fourth time in the past 32 such meetings.

Cristiano Ronaldo missed an early penalty, Sancho hit the crossbar and Fernandes squandered a glorious chance when he hit the post.

Overall, United had 30 shots, the most of any team in a single FA Cup match since the start of last season, finishing with 4.32 expected goals to Middlesbrough's 1.43.

United have now lost six of their past seven shoot-outs in all competitions and the Champions League is their remaining faint hope of silverware.

Despite the damaging loss, Rangnick felt there was not much to criticise in terms of the overall performance.

"We have played well in the last couple of weeks, in the league and also in the first half [against Boro]," added the German.

"I don't think we could have done a lot of things a lot better, apart from scoring more goals in the first half. We have to take our chances better with more quality than we did.

"The chance that Bruno had, if he had 10 chances like that in a game, he would score nine of them. He hit the post and I think he tried to place that ball almost too accurately into the corner of the goal.

"In the end things like that can happen. Of course he didn’t do that on purpose and for now our full focus must go on the other two competitions [the Premier League and Champions League].

"Of course the players are disappointed like we all are but again this is football, this can happen."

Nikola Vucevic was tasked with dominating the middle against the depleted Indiana Pacers and the Chicago Bulls center was up to the task.

Vucevic earned a 29th double-double of the season, scoring a season-high 36 points and adding 17 rebounds as the Bulls earned a 122-115 triumph on Friday.

DeMar DeRozan contributed 31 points to the cause against a Pacers side devoid of Goga Bitadze, Malcolm Brogdon, Isaiah Jackson, T.J. McConnell, Myles Turner and T.J. Warren due to injuries, while Domantas Sabonis is unavailable due to health and safety protocols.

The Bulls consequently remain top of the Eastern Conference after winning for the fourth time in six outings, with Vucevic going 16 of 21 from the field.

In credit to the Pacers, they were only trailing 65-62 at halftime and briefly led when Lance Stephenson landed a three-pointer with a little under three minutes of the third quarter remaining, but a 10-0 stretch in the fourth ensured the Bulls were in control.

Mitchell return inspires Jazz against out-of-sorts Nets

Donovan Mitchell missed eight straight games as a result of a concussion but made up for lost time as the Utah Jazz, fourth in the West, outclassed the out-of-form Brooklyn Nets 125-102.

Mitchell ended the game with 27 points on the back of eight-for-10 shooting, while he drained six three-pointers and added six assists in 22 minutes of action. His tally was a franchise record for most points scored under 22 minutes.

Bojan Bogdanovic was a valuable ally with 19 points and 11 rebounds, as the Nets were consigned to a seventh consecutive defeat.

James Harden (hamstring), Kevin Durant (knee), LaMarcus Aldridge (ankle) and Joe Harris (ankle) were all again absent for a Nets team who have plummeted to sixth in the East.

Doncic triple-double sparks Mavs comeback

Not for the first time in his career, Luka Doncic was the hero for the Dallas Mavericks as they overturned a 16-point second-quarter deficit to defeat the Philadelphia 76ers 107-98.

Doncic earned a 44th career triple-double, finishing with 33 points, 13 rebounds and 15 assists in a game that was paused for 44 minutes during the opening period after it was ruled one of the rims was crooked.

Reggie Bullock made a pair of big three-pointers down the stretch in a 20-point showing, while Jalen Brunson put up 19.

The Mavs snapped a two-game losing streak, while the 76ers - for who Joel Embiid had 27 points and 13 rebounds - have lost two on the spin for the first time since the middle of December.

Diego Schwartzman survived a scare from lucky loser Daniel Elahi Galan to reach the semi-finals of the Cordoba Open.

Top seed Schwartzman lost the first set to this Colombian opponent, but recovered to prevail 3-6 6-0 7-5.

Yet the Argentine still had to battle to clinch the decisive set, dropping serve when attempting to wrap up the match at 5-3.

He recovered from that setback and is just two wins away from his second title on home soil, having won in Buenos Aires last year.

Schwartzman will face qualifier Alejandro Tabilo in the last four.

Albert Ramos-Vinolas, seeded sixth, beat fourth seed Lorenzo Sonego in straight sets to book his place in the semis, where he will face Juan Ignacio Londero.

Ralf Rangnick said it was "incredible" that Middlesbrough's goal was allowed to stand as they knocked Manchester United out of the FA Cup on Friday.

The Championship side triumphed on penalties at Old Trafford after holding United to a 1-1 draw, Matt Crooks cancelling out Jadon Sancho's opener despite the ball striking Duncan Watmore's hand in the build-up.

The Red Devils were punished for missing a hatful of chances as they failed to win a home FA Cup match against a lower-league side for just the fourth time in the past 32 such meetings.

After Cristiano Ronaldo had missed an earlier penalty, a deflected Sancho strike put United in front, but they failed to build on that advantage despite dominating proceedings in the first half especially.

Overall, United had 30 shots, the most of any team in a single FA Cup match since the start of last season, finishing with 4.32 expected goals to Middlesbrough's 1.43.

Yet they found themselves level when Crooks turned in Watmore's lob, the goal allowed to stand after Watmore's clear handball was deemed to be accidental.

United continued to be profligate, Bruno Fernandes somehow hitting the post with the goal at his mercy and Anthony Elanga heading a clear chance straight at goalkeeper Joe Lumley.

It was teenager Elanga who missed the crucial kick in the shoot-out, firing his effort over the bar after the first 15 penalties had been scored.

United have now lost six of their past seven shoot-outs in all competitions and the Champions League is now their remaining faint hope of silverware for this season given they are 19 points off the Premier League pace set by Manchester City.

"In the end, the goal should never have been given. It's incredible that it stood," Rangnick told MUTV.

"It was a clear handball. I would not have needed VAR, it should have been seen by the referee himself but the VAR should not have given the goal.

"As far as I know, the referee and the VAR said it was not intentional, it was coincidental, how can it be coincidental if the hand is up there and he controlled the ball with his hand?"

Despite his frustration with the equaliser, Rangnick admitted United only had themselves to blame for their cup exit.

"We're really disappointed," he said. "The players, the staff, everybody. This was completely unnecessary. We should have killed off the game in the first half. We could easily have been 3-0 or 4-0 [up].

"We started well and played extremely well in the whole first half. Our movement and tempo of the game were exactly what we intended to do. But it was only 1-0 and a goal like this can always happen, although it shouldn't have happened from our perspective because we didn't defend well, we were too open in that counter-attack situation."

Boro boss Chris Wilder conceded he had expected Crooks' goal to be disallowed at first.

"We rode our luck and took our chances," he told ITV. "The decisions that are made through VAR have changed since I left the Premier League. I thought straight away it was handball. I thought it would be chalked off and [I am] delighted it wasn't.

"The FA Cup is alive and kicking, especially in Middlesbrough. I told the players it was all about making memories."

Alexander Zverev breezed into the semi-finals of the Open Sud de France by beating home favourite Adrian Mannarino for the loss of just one game.

The world number three needed just 50 minutes to swat aside Mannarino 6-1 6-0 to set up a last-four match with Mikael Ymer.

Champion at this event in 2017, Zverev's record in Montpellier moved to 9-1 and he has now won seven matches in a row against Mannarino.

Ymer, the world number 83, squandered one match point in his contest with Richard Gasquet but eventually came through 7-5 6-7 (6-8) 6-1.

The best entertainment came in the earlier match between Alexander Bublik and Roberto Bautista Agut, sixth seed Bublik eventually coming through 6-4 2-6 7-6 (7-4) after just over two hours on court.

He will face Filip Krajinovic for a place in the final, the Serbian having beaten Damir Dzumhur in straight sets.

At the Tata Open Maharashtra, rising Italian star Lorenzo Musetti was surprised by world number 95 Kamil Majchrzak.

The Pole, who defeated Musetti's compatriot Andreas Seppi at the Australian Open in straight sets, won 6-2 6-7 (5-7) 6-4 to set up a semi-final against Emil Ruusuvuori.

The other semi-final sees Joao Sousa, into the last four at Tour level for the first time since St Petersburg in 2019, face Elias Ymer.

 "I think I played a great match," said Sousa after beating Daniel Altmaier in straight sets. "I was very solid. I knew it was going to be a tough match, so I was prepared to run a lot."

Manchester United exited the FA Cup on penalties after a contentious 1-1 draw with Middlesbrough in the fourth round at Old Trafford.

Anthony Elanga blazed over to send Boro through 8-7 following United's seventh spot-kick defeat in eight contests, although they would no doubt argue the tie should not have advanced to that stage.

Ralf Rangnick might point to generous officiating from Anthony Taylor that did not punish Duncan Watmore's handball in the build-up to Matt Crooks' second-half equaliser for Boro.

But United's inability to add to a lead secured by Jadon Sancho was equally damaging, their 30 shots worth a combined 4.32 expected goals – an early Cristiano Ronaldo penalty among the misses as the Red Devils crashed out.

By the time Sancho made the most of Boro's latest piece of haphazard defending to break the deadlock with a deflected shot across Joe Lumley, United could have been two or three up.

Sancho clipped a delicate attempt onto the crossbar after Lumley spilled a long ball, then Anfernee Dijksteel clumsily brought down Paul Pogba in the box, only for Ronaldo to drag his spot-kick wide. Bruno Fernandes volleyed wildly over when played onside, too.

Chances continued to come and go after the 25th-minute opener, with Marcus Rashford letting Boro off the hook again early in the second half.

And that profligacy came back to bite United in bizarre circumstances when Watmore blatantly controlled Isaiah Jones' cross with his hand but directed a lob across the face of goal, allowing Crooks to steal in and net a leveller that the VAR did not overturn.

Fernandes pulled a straightforward finish against the foot of the post soon afterwards, failing to prevent an extra time period in which Dean Henderson was required to make a close-range stop from Aaron Connolly to reach the shoot-out.

Each of the first 15 kicks were scored, before Elanga finally failed, stunning the home support.

Simone Inzaghi scoffed at the idea Inter might kill off Milan's title hopes in Saturday's derby, as he claimed even Juventus remain in the Scudetto hunt.

A victory for Inter would move them seven points clear of Milan, while also having the advantage of a game in hand.

Inzaghi's Inter will be the home side at the San Siro stadium the teams share, and the Nerazzurri lead the way at the top of Serie A after losing just one of their opening 22 games.

It would be hard to see Milan coming back from defeat to their great rivals, but Inzaghi is not discounting the prospect.

Asked if three points for Inter would count out Milan, Inzaghi said: "I don't think so. There are another 15 matches to go and we all saw what happened in the first half of the season. We were seven points behind and drew the derby and still managed to close the gap."

Milan made a flying start to the season but were reeled in, with 2021-22 carrying distinct echoes of how the 2020-21 campaign panned out.

Then, it was Antonio Conte pulling the strings as Inter charged through to capture the title, and now it is Inzaghi's turn, with a first Scudetto of his coaching career beckoning.

He triumphed in Serie A as a player with Sven-Goran Eriksson's double-winning Lazio in 1999-2000, and is not getting ahead of himself this time.

"It's an important game and we know how much it means to the fans," Inzaghi said of derby day. "But there are 45 points and a lot of football to play before we can draw any conclusions.

"I played in lots of derbies and there's never a favourite. Tomorrow will be no different: it's a game that will be won by fine margins. It will come down to our motivation."

Inter have lost only one of their last 11 Serie A meetings against Milan. That defeat was a 2-1 setback in October 2020, with Zlatan Ibrahimovic scoring twice in the opening 16 minutes. Inter have won six and drawn four of those 11 games, with Milan keeping a clean sheet just once.

Most signs point to Inter giving up no ground to their city rivals this weekend. Their last Serie A home defeat was that 2020 loss to Milan, and they are undefeated in 28 games since in the competition when hosting.

Inzaghi won just three of 10 Serie A games against Milan while serving as head coach at Lazio, and his Inter side drew 1-1 with Stefano Pioli's Rossoneri earlier this season.

For obvious reasons, Inzaghi would dearly love a win this time. Napoli and Milan both enter the weekend as Inter's closest challengers, four points back and having played one game more than Inzaghi's men.

Despite this position of strength, Inzaghi said the title race was "all still open".

"Besides Milan and Napoli, there's Atalanta and Juventus, who are very good teams," Inzaghi told a news conference, according to Inter's website.

"Juventus have been doing really well in the last two months and they've made some great signings. All of the teams down to Juventus could win the Scudetto."

Juventus raided Fiorentina last week to sign Dusan Vlahovic, the exciting Serbian forward who hit 33 goals in Serie A in 2021, and that should fortify Massimiliano Allegri's fifth-placed Bianconeri for a push into the Champions League places.

Juve are 11 points off the top, also having played 23 games to Inter's 22. Atalanta are a point better off than Juve, occupying fourth spot.