Arsenal striker Robin van Persie will be out for a month after injuring his knee playing for Holland on Wednesday.
“The early signs are he will not be able to perform for us in the next four weeks,” manager Arsene Wenger told the club’s website.
“It is a big blow. I hope he will be back soon and we’ll do the maximum to get him back.”
Arsenal defender Philippe Senderos faces a fortnight out after picking up a back injury playing in Switzerland’s midweek friendly against the USA.
Van Persie will miss a number of key fixtures as the Champions League restarts next week and Arsenal face Liverpool and Manchester United after Saturday’s game with Bolton.