The Red Devils secured a second-placed finish in the Premier League this season as they enjoyed their strongest finish since Sir Alex Ferguson retired back in 2013.
Manchester United will be aiming to finish the campaign on a high by beating Chelsea FC in the FA Cup final at Wembley on Saturday afternoon.
Attentions will then inevitably turn towards the summer transfer window and the comings and goings at Old Trafford.
The Red Devils are likely to want to make a number of signings as they look to try and build a team capable of winning the title next season.
But former defender Neville feels that it will be almost more important for the Red Devils to get rid of the players who are not up to scratch at Old Trafford.
Speaking to Sky Sports on Sunday, Neville said: “The question at Manchester United is which players do you keep and which don’t you keep. Who are the ones that Jose Mourinho thinks don’t have the mentality and who are the ones he feels do have it?
“I am confused by that, and Jose Mourinho probably is at times too, because the performance levels are up and down so much.
“It’s not just game to game but half to half. Look at the games against Manchester City and Crystal Palace, you see them at such a low and then such a high.”
Manchester United won both the Europa League and League Cup under Mourinho last season and they will be aiming to end the campaign on a positive note by beating Chelsea FC on Saturday evening at Wembley.
MORE: Man United latest news
MORE: Arsenal latest news
MORE: Chelsea latest news
MORE: Liverpool latest news