United, who had not lost since January, eventually fell to a 3-1 defeat against the Blues.
Phelan was seen gesturing on the bench after Lindelof was slow to react, allowing Olivier Giroud to flick the ball goalwards.
But De Gea has also been criticised after his weak hand wasn't enough to stop the ball trickling in.
Phelan was clearly unimpressed as he sat next to manager Ole Gunnar Solskjaer and coach Kieran McKenna.
— utdreport (@utdreport) July 20, 2020
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