Arsene Wenger plans to play Gabriel at right-back until Hector Bellerin returns, admitting that Carl Jenkinson "has no confidence" after a couple of poor performances.
Jenkinson was heavily criticised after Arsenal's 2-0 loss to Southampton in the League Cup on Wednesday and had been dropped from the squad completely for the previous Premier League game against Bournemouth, when Mathieu Debuchy made his first appearance of the season.
However, Debuchy suffered a hamstring injury in that game, leaving Wenger without his top two right-backs as Bellerin is out for at least another two weeks with an ankle problem.
Wenger said he expects to have Bellerin back for the home game against Manchester City on Dec. 18, but is planning to use a stop-gap measure until then.
Because even though Jenkinson is now the only true right-back who is fit after making his own return from having knee surgery in January, Wenger said he will play centre-back Gabriel -- or possibly 19-year-old Ainsley Maitland Niles -- in the position until Bellerin is back.
Wenger said Jenkinson simply needs more time to get back to his best after being sidelined for so long.
"What he's going through at the moment for me is a bit normal, but very difficult to live [through] for a player. Why? Because you think you are there. ... And then you play, and you realise that you are not as good as you think you should be," Wenger said ahead of Saturday's game at West Ham.
"And you lose confidence. And he is going through that period at the moment, he has lost confidence. Because the Jenkinson you see at the moment is a Jenkinson who can play, but he is not completely Jenkinson because he has no confidence."
Wenger used his last substitution against Southampton to replace Jenkinson with Maitland-Niles, instead of sending on a striker to help erase a two-goal deficit, and the defender was subject to a torrent of criticism on social media from fans after the game.
However, the Arsenal boss said he still expects Jenkinson to fight for a place in the first team later this season and must stay focused until he's back to his best.
"He will be in and out [of the squad], and after one or two months he will make the step and play," he said. "It's natural, but it's very difficult to live [through]. I think today it's even more difficult because you get quickly hammered by everybody on social media. I hope he doesn't read all that, and focus on his game."
The 23-year-old Jenkinson spent the past two seasons on loan at West Ham to get more Premier League experience after Wenger bought Debuchy and saw Bellerin emerge as one of the most promising right-backs in Europe.
Now he faces a situation where he won't play, even though both of his two rivals for the position are injured. And Wenger acknowledged that could be a further hit to his confidence.
"Well yes. Look, the best way to help them is to respect the fact that [you shouldn't] play them when they are not competitive," he said. "Because to play them when they are not completely ready is even worse."
Gabriel only made his first appearance at right-back when replacing Debuchy against Bournemouth, while Maitland-Niles has started there once, in the League Cup.
There is also a slight question mark over whether Gabriel is mentally ready to play Saturday after mourning friends at Brazilian club Chapecoense who died in the plane crash in Colombia this week. Gabriel recorded a message to the families of the victims after playing against Southampton, and Wenger said he would talk to the Brazilian to see how he feels about playing.
"I will have a chat with him today. If he is in the right frame of mind, he will play," Wenger said. "He has sent a very emotional message to the families of people involved in this crash, but he still played on Wednesday night and I think if he has recovered well physically, and mentally as well, I will play him."