Eric Bailly is aware that Marcos Rojo's return from injury will improve competition at Manchester United and the defender stressed the situation would benefit the Red Devils.
The Argentine international suffered a knee injury in the Europa League clash against Anderlecht in April. Zlatan Ibrahimovic, who was re-signed by United in the summer, also suffered a knee injury in the same clash.
Rojo and Ibrahimovic underwent surgery in May and are currently recovering on the sidelines. Jose Mourinho earlier vowed to not rush the versatile defender back to the squad and confirmed he would only return in December.
Without Rojo, the United manager has the services of Bailly, Phil Jones, Chris Smalling and Victor Lindelof as the four recognised centre-backs in the squad. The Ivory Coast international believes it is very "crucial" to improve competition for a place in the starting lineup.
"Of course [competition for a place in the starting XI is good], I think it's very crucial. It's very important too for us young players in order not to relax," Bailly told United's official website.
"We have to keep on working because at any given moment the others might see their chance and take it. It's good competition, it creates a positive spirit and helps the team, that's what we're aiming for."
"It's good, there's a good relationship between Phil and me, and with the other two defenders, Victor Lindelof and Chris Smalling, even though we've not had the chance to play together yet.
"It's fine in my view because there are four of us defenders and everyone is ready to make the most of the opportunities the manager gives us. To defend as well as possible and concede less goals, that's the aim for all of us."
United have the joint best defensive record in the Premier League with Manchester City. Bailly and Jones' partnership at the heart of the back four has been very crucial. The 20-time English champions face Liverpool at Anfield after the international break.