Louis van Gaal praised Manchester United for fighting fatigue to come through a "very difficult" clash with Wolfsburg as 2-1 victors.
Having entered the game desperate for a win after losing their opening Champions League Group B fixture at PSV, United made a nightmare start as Daniel Caligiuri gave the visitors a fourth-minute lead.
Yet the hosts found a riposte, Juan Mata converting a penalty before superbly setting up Chris Smalling to make it 2-0 just after half-time.
The latter was then required at the other end, with United coming out on top thanks to a dogged defensive rearguard.
That pleased boss Van Gaal, who had called on his side to win all of their European fixtures at Old Trafford.
"It was very difficult," he told BT Sport. "They scored early, but then we did very well and created a lot of chances that we didn't finish.
"We created many more chances. [Wayne] Rooney and [Memphis] Depay could also have scored in the first half, and then the game's finished.
"At the end we were suffering. A lot of players are very tired due to the accumulation of a lot of matches. But we still never gave too many chances away."
