Arsenal have confirmed centre-back David Luiz went under the knife on Sunday after a knee injury caused him to miss the weekend's 3-0 loss to Liverpool.
The Gunners were completely mauled by Jurgen Klopp's defending champions, lacking ideas at both ends of the field as they slumped to an emphatic defeat which left them tenth in the Premier League standings.
Manager Mikel Arteta will be keen to see an immediate response, but he will have to get that without Luiz as the club confirmed on their official website that the Brazilian has undergone a 'small procedure' to address his issue.
"The procedure has been a success and David is now back at home rehabilitating," a statement read. "He will be able to return to daily support and recovery with our medical team at the training centre in the coming days."
Luiz is obviously set for a spell on the sidelines, but because of the size of the surgery, he is not expected to be out for long and Arsenal are hopeful that the veteran defender will be available in the coming weeks.
His involvement in both legs of the Europa League quarter-final with Slavia Prague, which are scheduled for April 8 and 15, appears in real jeopardy, and Luiz could also miss Premier League clashes with Sheffield United, Fulham and Everton if he remains sidelined for the rest of the month.
Luiz's fitness is not the only concern Arteta has to deal with. Left-back Kieran Tierney limped off in the Liverpool game with a knee injury of his own, after which the boss admitted he was unsure of the severity.
"He felt something in his knee," he said. "He was in pain so it looks like he will be injured but we don't know how long for."
It was the Scot's sixth game back for the team after returning from a knee injury which he picked up in January, so Arteta will be hoping that there is no long-term issue which needs addressing.
The defeat leaves Arsenal down in tenth in the Premier League, nine points adrift of the top four and seven points behind Tottenham in fifth.