Manchester City unclear when Sergio Aguero will return after striker undergoes knee surgery

Manager Guardiola says it is too early to put a timescale on when the 32-year-old could play again

Player ratings from Manchester City 5 Burnley 0: Ederson - 6: A virtual spectator who never had a save to make. AP

Oleksandr Zinchenko - 7: Full-back was always looking to get forward and had couple of half chances to score. PA

Fernandinho - 7: Beautiful long ball out of defence to put Mahrez on his way for his opening goal. Getty

Joao Cancelo - 7: Decent show from the big-money summer signing but given yellow card for clumsy second-half challenge on Vydra. Reuters

Nicolas Otamendi - 7: Easy night as the City defence was rarely troubled. Getty

Rodrigo - 7: Solid if unspectacular. Getty

David Silva - 7: Got on the end of a beautiful team goal to make it 4-0. Usual classy performance from the Spaniard. AFP

Phil Foden - 9: Two goals and played beautiful reverse pass to open up Burnley's defence for the fourth. Man of the match in his fourth Premier League start of the season. Reuters

Bernardo Silva - 7: Missed glorious first-half chance on his weaker right foot but set up namesake David for the fourth.

Riyad Mahrez - 8: Brilliant skill and finish for his first goal. Cool penalty for his second. Getty

Sergio Aguero - 5: Game to forget for the prolific striker. Made little impact - one chance that was blocked - before going off injured in the incident that earned City a first-half penalty. Reuters

Gabriel Jesus (sub 45) 6: Replaced the injured Aguero and will have been disappointed not to have got involved in the goal-fest. PA

Aymeric Laporte (sub 61) 7: Never troubled by Burnley's powder-puff attack

Kevin de Bruyne (sub 61) 7: A few quality touches and passes from the Belgian. EPA

Leroy Sane (sub 79) NA: Came on for Foden but little chance to make impact. EPA

Nick Pope - 5: Left badly exposed by his creaking defence. Reuters

Matthew Lowton - 5: Tough night against a rampant City attacking performance. EPA

Charlie Taylor - 5: Started really well against Mahrez but was then turned inside out for his first goal. AFP

James Tarkowski - 5: Part of an unusually disorganised Burnley defence. AFP

Ben Mee - 6: Harsh penalty given against him by VAR after challenge on Aguero. Getty

Josh Brownhill - 5: Could have done more to try and block Foden's opener for City. Booked. AFP

Ashley Westwood - 5: Worked hard but up against quality opposition. AFP

Jack Cork - 5: Chasing shadows for most of the match. PA

Dwight McNeil - 6: Tried to make things happen early on but disappeared the longer the game went on. Getty

Matej Vydra - 6: Thankless task up front but ran his heart out. Getty

Jay Rodriguez: 5: Tough for the Burnley attackers as City dominated the game, Hooked after an hour. Reuters

Erik Pieters (sub 60) 6: City only managed one more goal after the defender came on for Rodriguez. Reuters

Max Thompson (sub 79) NA: Replaced Vydra but no chance to make an impact with game already long gone. EPA

Manchester City's Argentina striker Sergio Aguero has undergone knee surgery and it was not clear when he will be fit again, admitted manager Pep Guardiola.

The club's record goalscorer limped off during Monday's 5-0 Premier League thrashing of Burnley at the Etihad Staidum.

Guardiola said after the game he feared the 32-year-old could miss the rest of the league season which ends in July.

The Argentine flew to Barcelona on Tuesday to have specialist Dr Ramon Cugat look at his knee and City will be hoping the player might return in time for the Champions League restart in August.

Asked on Wednesday if Aguero would be fit for the resumption of the European football's premier club competition on August 7-8, City's Spanish manager said: "I don't know right now. Once he has finished the surgery we will know the time Sergio will come back to play with us."

Guardiola had suggested that the Argentine would have the operation on his left knee on Thursday but Aguero later tweeted suggesting the procedure had already taken place.

Posting a message alongside a picture of himself in a hospital bed, Aguero wrote: "Everything went well, and I'll soon begin recovery. A big thanks to Dr Cugat and his team – and to all of you for your support."

City lead 2-1 against Real Madrid after the away leg of their last-16 match and are hoping to reach the 'Final Eight' of the competition which will be held in Lisbon.

Guardiola said City had plenty of options, with Gabriel Jesus the only main striker fit and ready but Ilkay Gundogan and Raheem Sterling are able to slot into the role.

The manager indicated defender John Stones was close to a return after an ankle injury but was unlikely to face Chelsea.

"He is on the pitch training and getting better," said the Spaniard. "Hopefully in the next few days he can play in the team."

A final decision on whether City's clash against Liverpool next Thursday takes place at the Etihad Stadium or a neutral venue is expected to be made before the end of the week.

Asked about the possibility of the game being moved elsewhere, Guardiola said: "We will follow the Premier League instructions. All the protocols they've said, we're going to do."