Solskjaer said: "I think you can see it was two teams towards the end that were tired. End to end and an open game - sometimes that doesn't suit us.
"We're delighted to beat Wolves finally. Juan Mata is different class. He's got the skill, composure and even pace."
On the note handed to Mata during the first-half, the manager added: "A couple of times we went out of shape - we adjusted it for five/10 minutes before half-time.
"Dan [James] had three or four great opportunities one-on-one with the keeper. Fair play to our boys we created them but we didn't take them."
Asked if the decision to play Rashford backfired, Solskjaer said, "Yes it backfired. You got to take them once in a while. He'll be tested in the next few days - we have to see for Sunday. He couldn't run. He struggled a little bit with his back and got another knock. It didn't help."