Manchester City manager Pep Guardiola has confirmed that Kyle Walker was taken off with an injury in Saturday's draw with Aston Villa in the Premier League.
Despite his side's impending Champions League opener with Sevilla and busy schedule, Guardiola opted to keep Walker and Joao Cancelo in their usual full-back roles.
However, with 10 minutes left to go in the contest, 32-year-old Walker signalled that he could not continue and was replaced by Nathan Ake - just back from injury himself.
Speaking to the press after the game, Guardiola confirmed that Walker had suffered an injury of an unspecified nature, but he could not comment on how long the right-back might be out for.
"He had some problems in the first half and in the second and he could not continue. We will see how he is. I didn't speak to the doctors," Guardiola explained.
While the severity of Walker's issue remains unclear, the former Tottenham Hotspur man has emerged as a doubt for Tuesday's trip to the Estadio Ramon Sanchez Pizjuan.
Walker has remained an integral player for Man City despite the form of Cancelo, who continues to ply his trade on the left-hand side given the form of his compatriot.
Walker boasts a total of six goals and 17 assists in 222 appearances for Guardiola's side since making the move from Tottenham in 2017, and he won his fourth Premier League title last year.
Erling Braut Haaland's 10th Premier League goal of the season put Man City in the ascendancy at Villa Park after the break, but Steven Gerrard's side hit back through a powerful Leon Bailey drive.
The Lions were then incorrectly denied a second goal from Philippe Coutinho, who was adjudged to have been offside in the build-up to a terrific long-range strike, but replays showed that the Brazilian was actually onside.
Man City missed the chance to rise to the top of the Premier League table at Villa Park, but Guardiola is still satisfied with a 14-point haul after six games of the new season.
"I am a positive person in general. We have dropped four points so far and now we have the Champions League. Every game away is difficult in the Premier League - Newcastle, today - I know how difficult it is and the opponents are really good," Guardiola added.
"The titles we won in the past were difficult and this will be no exception. The people talk, but I know this is just the beginning. A lot of things are going to happen this season."
Arsenal can now move four points clear of the reigning champions at the summit if they get the better of Manchester United at Old Trafford on Sunday afternoon.
Guardiola also has Aymeric Laporte (knee) out of contention for the trip to Sevilla, but the City boss will hope to have Kalvin Phillips back in the squad following a shoulder injury. body check tags ::