Anthony Martial's strained relationship with Jose Mourinho may be approaching breaking point after the Portuguese pointed the finger at Martial and Marcus Rashford for their poor displays in the 1-0 defeat at Brighton.
Martial's future at Old Trafford was already in doubt, with Chelsea, Juventus and Inter Milan among the teams interested in signing the prodigiously-talented young forward.
And Mourinho, who was desperate for his side to secure second place and to be given a selection dilemma ahead of the FA Cup final against former club Chelsea, was left less than impressed with what he saw on Friday night.
"For many months you are always asking me why this player doesn't play, why that player doesn't play, why this player is on the bench, why always Lukaku?
"You should be disappointed more than me because probably I know my players better than you, and probably you don't know them so well to be always with these questions.
"It was a difference in the desire to fight for the targets. They had one target, to get the points and celebrate their Premier League survival.
"We had the target to get the points to finish second, and they showed that for them it is more important than for us to finish second."
Martial is not a player that the Old Trafford club's hierarchy want to sell after investing nearly £50m in him, and he is still seen as a young player with immense talent. Mourinho, however, is somewhat less sold on the former Monaco forward.
United have now lost away to all three promoted teams this season after a Pascal Gross goal earned Brighton the win they needed to guarantee their survival.
The visitors knew a victory would all but secure second spot, but Mourinho made six changes to his line-up - and it backfired badly.
Romelu Lukaku was missing for United as expected but Alexis Sanchez also sat out with an injury.
German midfielder Gross, Albion's undisputed player of the year, fittingly hit his seventh goal of the season to take the Seagulls to the magic 40-point mark
In the 56th minute Jose Izquierdo skipped past Matteo Darmian and stood a cross up towards the far post.
David De Gea pushed the ball up onto the head of Gross and although Marcos Rojo hooked it clear from underneath the crossbar, goalline technology confirmed it had crossed the line.
Chris Hughton's side can now look forward to another season in the top flight having assured they are mathematically safe ahead of trips to Manchester City and Liverpool
"Normally when you win this type of game it's because you've played at a good level and United haven't, maybe your keeper has to make some good saves and they've missed some chances," said Hughton.
"But they didn't have a clear-cut chance in 90 minutes, and Maty Ryan only had to make a couple of decent saves. We were good value for the win. That's almost as important. It's given us Premier League survival.
"So it's a relief that we've done it now, but I'm also really proud of a group of players."
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