Ralf Rangnick has added coach Chris Armas and sports psychologist Sascha Lense to his backroom team.
Armas was New York Red Bulls head coach from 2018 to 2020 and was manager of Toronto FC until he was sacked in July this year.
Rangnick worked with Lense at RB Leipzig.
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"We have decided to bring in a sports psychologist, Sascha Lense, I worked with him for three years at Leipzig," Rangnick told reporters.
"We know each other. He will be introduced to the team as soon as he's got his visa. I hope we'll have him on board by Thursday.
"I will also have another assistant coach with Chris Armas. He was at New York Red Bulls when I met him. He will again hopefully be able to join us in the next few days."
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Rangnick says he needed to bring in a sports psychologist and that is it a "logical" step.
"I don't know what the situation is like in England," he added.
Most German clubs have employed a psychologist. For me it is logical. If you have special coaches for goalkeeping, strikers, fitness, you should also have an expert for the brain.
"Not to put them on the red sofa, or hold hands, for me it's about helping the players know the brain should assist the body, not work against it.
"For me everyone in the team should think the right way. Whenever we speak about football, the major part is up here [the brain].
"He's a former player, hands on, not caught too much in the theory. Having worked together at Leipzig I know we can benefit from him. For me it's vital on top level you should have the best person possible on this job."
United face Young Boys in their final Champions League group match on Wednesday night. Victory will seal United top spot in Group F.
Rangnick has confirmed Donny van de Beek and Dean Henderson will start the match.
"To start with they will both pay tomorrow in the first XI," Rangnick said. "Donny came on as a sub [against Crystal Palace], and I know Dean is a very ambitious goalkeeper.
"We definitely need two goalkeepers, and then with Tom (Heaton) and Lee (Grant) we have four. I have to get to know the players first to finally assess them. Right now I'm happy to have them on board."
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