Shinji Kagawa admits he must prove himself to Manchester United boss David Moyes or risk losing his place at Old Trafford.
Kagawa was substituted at half-time in United's defeat to West Bromwich Albion on Saturday, adding further doubt for the Japan international who has failed to establish himself in the starting line-up this season.
The 24-year-old, who is hoping to break into the fold for United's Champions League trip to Shakhtar Donetsk on Tuesday, concedes he must improve or risk finding himself permanently on the outer.
"I have to take this like some kind of message [from Moyes]," he said. "I need to improve more and more, or I cannot survive at this club. I have to take this in a positive way and keep trying to do my best.
"I thought that I would have been able to find some space to create the chances in the second half [against West Brom]. In that sense I was disappointed [to have been substituted.
"Sure, I wasn't involved that much, I didn't touch the ball enough but I was trying to be patient so I didn't feel that bad."