Manchester United head coach Erik ten Hag has said that Scott McTominay's form this season has prevented Casemiro from earning regular starts since his arrival.
Casemiro is yet to start in the Premier League this season, with all four of his outings in England's top flight coming off the bench, with his only appearance in the first XI coming against Real Sociedad in the Europa League on September 8.
There have been calls for the 30-year-old to now be handed a starting role following Sunday's 6-3 defeat to Manchester City in the Premier League.
Ten Hag has insisted that Casemiro's lack of starts are not a reflection on him, with McTominay's form making it difficult for the manager to change his midfield.
"First of all, it doesn't make a difference: Europa League, Premier League. We have to win all the leagues and all the cups. So, we will play tomorrow our best team and we have to construct the team because also we want a competitive culture in our team, in this club," Ten Hag told reporters ahead of Thursday's Europa League contest with Omonia.
"I said already before, it had nothing to do with Casemiro, it was all to do with Scott [McTominay] because when you look at Brentford, he wasn't in the team, and we lose.
"Then on the day that Casemiro signed, we won. We play six games and we win five. And in five games, [McTominay] played. In one game he didn't, and that was against [Real] Sociedad. So for me, that was logical because it's competition in the team.
"So, for me, it wasn't a choice. He performed really well, he developed really well and it had nothing to do with Casemiro. But I'm sure Casemiro will play a really important role.
"We know all his background, we know all the titles he won. You see every day in training, he can contribute in this team and he will be a really important player for this team. So we will see what will happen but I'm convinced that will happen."
Speaking after the derby defeat to Man City, Ten Hag said that Casemiro's introduction into the starting side would have to come "in a natural way".
"I'm sure it will be important for us in the long and short-term, he will find himself in the team but it has to come in a natural way," said the Dutchman.
Both Casemiro and McTominay have been included in the squad for Thursday's European contest with Omonia, with the Red Devils looking to make it back-to-back wins in the competition.
The 20-time English champions will then switch their attention back to the Premier League, facing a trip to Goodison Park on Sunday evening to tackle Everton, who are now unbeaten in their last six league games, winning their last two against West Ham United and Southampton. body check tags ::