Arsenal striker Alexandre Lacazette is expected to miss between four and six weeks with a knee injury, the club have confirmed.
The Frenchman had an arthroscopy on his left knee in London on Tuesday morning following Saturday's 1-0 defeat against Tottenham.
The minor procedure was reportedly a success and the 26-year-old will now undergo a period of rehabilitation.
The injury blow comes following a disappointing run of form and a run of just one goal in ten league games.
Lacazette was criticised after Saturday's North London derby loss after missing two chances in the second-half.
And manager Arsene Wenger admitted after the game that the arrival of Pierre-Emerick Aubameyang might have had an impact on his confidence.
"For him, one against one with the goalkeeper, he is a good goalscorer," said Wenger - quoted by the Independent. "He has gone through difficult periods before. He works hard in training, works on his finishing.
"I don't know what happened, did he not touch the ball well? It can happen, it is a fraction of a second.
"Maybe the confidence is not at its highest because he has seen a competitor [Aubameyang] coming in for him."
He added: “He created two chances today. That is a quality as well. He will score goals. He is a goalscorer, he scored goals in his whole career. He will score again.”
Lacazette has scored only nine goals in 26 Premier League appearances this season since his £55m arrival from Lyon last summer.