Manchester United boss Erik ten Hag explained changing his substitute Alejandro Garnacho during victory over Crystal Palace.
The Argentine, 18, was taken off with just three minutes of normal time left on the clock and replaced by Harry Maguire, just 28 minutes after stepping off the bench himself. Garnacho had come on in the 59th minute to replace Wout Weghorst.
On how he adapted to Casemiro's red card and the subsequent Palace onslaught, Ten Hag said: "First we had to see how they changed, then you have to anticipate and see how we can close, how to be compact, how we close the gaps, how we get away from our goal but also still have a threat in attack. I think we had to change something.
"It's not always nice bringing off a player who we brought on but it's in the interests of the team and the player has to accept that."
Explaining why he had earlier brought Garnacho on in place of Weghorst, the United boss added: "He [Weghorst] played excellently. He was strong in putting pressure, in being a point of contact. We were able to continue playing through him. Only at a certain point do you switch tactically.
"To put an opponent who has focused on Weghorst against a different type of player.... I think it had an immediate effect."