The Danish goalkeeper has been preferred to the Spaniard in the past two Premier League matches and is looking to keep his place when United meet Galatasaray in their Champions League opener tomorrow night.
"At this point I see David's and my roles as co-workers rather than No.1 and No.2," he said.
"He has his strengths and I have mine and the gaffer is world class at picking the right teams and I trust in that and I accept his decision.
"I'm happy to play," he added. "Look at this place, it's amazing to play in front of this crowd. It's so historic and I'm just happy to play whenever I can."