Manchester City fear Benjamin Mendy could be ruled out for longer than first thought as £52m summer signing heads to Barcelona for further tests

• e-mail

Benjamin Mendy is heading to Barcelona on Wednesday for further tests on a knee injury amid fears it could be worse than first anticipated.

The Manchester City defender, who joined from Monaco for £52million in July, was forced off during the 5-0 thrashing of Crystal Palace on Saturday.

Mendy's knee was heavily swollen after a challenge by Andros Townsend and a first scan proved inconclusive.

Benjamin Mendy immediately clutches his right knee after going into a challenge on Saturday

Physios rushed to Mendy's aid, while countryman Yohan Cabaye also checked on his welfare

Mendy was able to limp off the field and initially his injury did not appear to be overly serious

City medical staff hoped the problem was an impact injury but more tests should determine whether there is any ligament damage.

The France international will be seen by knee specialist Ramon Cugat, who recently aided Ilkay Gungodan's long-term recovery.

City sources stress they will not know the full extent of the damage until the end of this week.

Mendy's absence would represent a blow to Pep Guardiola, who describes Cugat as 'the best doctor in the world'.

Kevin De Bruyne and Vincent Kompany have also been seen by Cugat since Guardiola's arrival last year.

City spent in the region of £130m on three signings at full back - Mendy, Kyle Walker and Danilo - but the news means Guardiola is now down to just two for the time being.

Danilo replaced Mendy against Crystal Palace and is likely to step in for the foreseeable future

Mendy has already become a fans' favourite on and off the pitch since joining Manchester City

Bacary Sagna, Pablo Zabaleta, Gael Clichy and Aleksandar Kolarov were all allowed to leave over the summer.

The Catalan suggested on Monday that he has a plan for this eventuality, with Fabian Delph utilised at left back over the last week. City could operate with three central defenders more often but are also short on cover in that department.

'Fabian can help us a lot,' Guardiola said. 'We are going to find a solution. He is a midfield player but he can play left back.

'Last season most of the times he was injured but when he played at Stamford Bridge or against Hull always he played at a high level.'

Manchester CIty boss Pep Guardiola is now facing significant problems at full back

Kyle Walker is another full back City recruited in the summer, while letting four leave the club