Mateo Kovacic tests positive for Covid one day after returning to Chelsea training

Croatian midfielder had been out of action since late October with a hamstring injury

Mateo Kovacic remains absent for Chelsea after testing positive for Covid-19 while recovering from a hamstring injury. AFP

Chelsea manager Thomas Tuchel revealed he will be without five players for their Champions League trip to Zenit St Petersburg, including midfielder Mateo Kovacic, who tested positive for Covid-19 just one day after returning to training.

Kovacic, 27, had been out of action since late October with a hamstring injury and Tuchel had hoped to ease him back into action this week. However, the Croatian returned a positive coronavirus test shortly after rejoining his teammates on the training ground and has now entered isolation.

"We have bad news because Mateo was in training yesterday and with a big smile and it was a pure pleasure to have him back," Tuchel said during his pre-match press conference on Tuesday..

"But he tested positive today, for coronavirus, so he's quarantining for a few days. So it's a huge setback for him personally and for all of us."

N'Golo Kante remains sidelined with a knee issue, while Jorginho has been forced to play through the pain of a back problem and will now miss Wednesday's Champions League trip to Zenit, leaving Tuchel short of central midfielders.

"Jorginho is out with back pain and we played with that pain against West Ham United," Tuchel said. "He’s come from the Champions League final, the Euros and straight into the Super Cup, so we expected there to be a stage where he suffers a little with being overloaded.

"We had a bit of an acute overload due to injuries and the schedule. Due to our injuries in some position, like central midfield, when we struggle. The game tomorrow is not the problem, it's more the game that comes up on the Saturday."

In addition to his absent midfielders, Tuchel will also still be without central defender Trevoh Chalobah and wing-back Ben Chilwell.

Chelsea, the reigning European champions, have already qualified for the knockout stages of the Champions League and will be confirmed as winners of Group H if they equal or better Juventus's result against Malmo on Wednesday.

West Ham v Chelsea player ratings

WEST HAM PLAYER RATINGS: Lukasz Fabianski – 6. Little chance with Silva’s header and while Mount’s finish was exquisite, no keeper wants to be beaten at his near post. Reuters

Kurt Zouma – 7. Solid against his former club, making crucial interceptions and blocks, and reading the game well. Injury ended his game prematurely. Reuters

Craig Dawson – 6. Got stuck in and stood up well in the physical battle against Lukaku in the second half. AP

Issa Diop – 7. Helped West Ham keep their defensive shape as Chelsea dominated possession and tried to work openings. AFP

Vladimir Coufal – 7. Put in a disciplined and dogged performance but was unable to venture forward much. PA

Tomas Soucek – 6. Usually poses a big goal threat from midfield but was subdued by Chelsea’s domination of possession. AFP

Declan Rice – 7. Had a good game in the middle of the park. The England international once again proved he can more than hold his own against the big teams. AFP

Ben Johnson – 6. Had his hands full trying to deal with James and Mount. As such, played more as a full-back than wing-back. Went off injured just before the break. Getty Images

Jarrod Bowen – 9. Brilliant finish to score West Ham’s second and could have got a brace, only to shoot wide when at full stretch. Pulled Chelsea apart in the second half. Getty Images

Manuel Lanzini – 7. Good composure to convert the penalty for West Ham’s equaliser. Beyond that, a quiet game from the Argentine. AFP

Michail Antonio – 8. Ineffective in the first half, Antonio was a player transformed after the break. Showed great hold-up play in the build-up to Bowen’s goal and his movement allowed Masuaku the space to score the winner. Bullied Hudson-Odoi. AP

SUBS: Arthur Masuaku (On for ohnson, 45+2’) – 7. Scored his first ever Premier League goal with a miss-hit cross that dipped into the Chelsea goal. AP

Pablo Fornals (On for Zouma, 71’) – 6. Ineffective 20 or so minutes. Getty Images

Said Benrahma (On for Lanzini, 85’) – N/A Reuters

CHELSEA PLAYER RATINGS: Edouard Mendy – 4. Rare blunder from the goalkeeper who dallied on the ball then hacked down Bowen for the West Ham penalty. Got his positioning all wrong for Masuaku’s winner. Bad day for the usually reliable Senegalese stopper. AFP

Andreas Christensen – 5. Given the run around by Antonio and never looked settled. Booked late on for a foul on the Hammers forward. PA

Thiago Silva – 8. Scored the opener with a typically fine header before minutes later clearing a West Ham effort off the line. Stayed composed even as chaos ensued around him. AFP

Antonio Rudiger – 6. Plenty of strong tackles and drove the ball up the pitch but lacked his usual dominating presence. AFP

Reece James – 6. One of the form players in the Premier League but was not at his best at the London Stadium. AP

Marcos Alonso – 5. Quiet game from the Spaniard. Didn’t offer all that much in attack and never entirely comfortable in defence. Replaced by Pulisic. AP

Jorginho – 5. Loose and unnecessary pass back to Mendy which resulted in the West Ham penalty. Second big error in the space of seven days. AP

Ruben Loftus-Cheek – 7. Won the ball and started the move for Chelsea’s second. Superb in the first half but his impact faded in the second. AFP

Hakim Ziyech – 7. Pure class to set up Mount’s volley: lovely touch, created the space on his left foot, and pinged a stunning cross to find his teammate. Ziyech at his irresistible best and looked threatening throughout. Will be disappointed to have been substituted. AP

Mason Mount – 8. England man produced a classy volley to restore Chelsea’s lead. Second goal in a week, Mount looks like he’s rediscovered his scoring form. Also delivered the corner for Siva’s opener. Getty Images

Kai Havertz – 6. Had a couple decent chances and looked dangerous when he broke through West Ham’s defensive lines but picked up an injury just before the break and was replaced by Lukaku. Getty Images

SUBS: Romelu Lukaku (On for Havertz 46’) – 5. Working his way back from injury and was starved of service. Chelsea need the Belgian firing. AP

Callum Hudson-Odoi (On for Ziyech 64’) – 5. Deployed at left wing-back and his defensive deficiencies were exploited by Bowen and Antonio. AP

Christian Pulisic (On for Alonso 72’) – Looked lively and tried to get on the ball but no real contribution of note. PA