West Ham striker Michail Antonio feels David Raya's form at Arsenal is being influenced over doubts about his status.
Raya conceded twice at Chelsea and also once in last night's Champions League win at Sevilla with goalkeeping rival Aaron Ramsdale on the bench.
Antonio insists Raya's shaky form is due to not having the security of knowing he is manager Mikel Arteta's first-choice.
He told BBC Sport: "If he makes a mistake in one game he's human. If he makes a mistake in another then Ramsdale will have to look at it.
"As a manager you should have your number one and then have their back and give them at least a second chance. You have to give your player some faith and he needs to trust that you will.
"He's [Raya] no longer nervous, he's not going to be on the pitch all frantic because he knows he has the trust of the manager. He can do the job that needs to be done because he's [Arteta] bought him in to play football.
"I feel he needs to have the confidence of the manager to be out there and play those passes and play the way the manager wants him to play."