Everton boss Ronald Koeman says he wants a reaction from Ross Barkley after he was left on the substitutes' bench during the match with Manchester United.
The attacking midfielder, 23, watched on from the dugout as his side battled back to draw 1-1 with United in the Premier League on Sunday.
That was the latest development in a campaign which has seen Barkley regularly criticised by Koeman and lose his place in the England squad.
Speaking ahead of Saturday's match at Watford, Koeman suggested it was Barkley's performances, rather than his attitude, that were the main concern.
"Sometimes it can be a tactical reason, sometimes I expect more from Ross Barkley," Koeman said.
"But I expect more from other players offensively. He needs to accept it. The reaction he needs to show on the training pitch.
"That's the best way. He is always trying to show his best, but it is not always about the mentality of the player - it is about tactics, his movement, his productivity and those can all be reasons he did not start last week.
"He's part of the team. He played a lot. He did not play last weekend. If you like to play you need to show that to the manager during the whole week.
"He is trying to do that, but he is one of the players that needs to show more productivity."
Everton sit eighth in the table, but have only won once in their last nine league matches.