Portuguese winger Nani had looked very lively in the opening half an hour before he complained of a tight groin muscle, while Evans suffered a knock to his ankle early in the second half.
Moyes confirmed to MUTV after the match: "Jonny actually got kneed on the ankle. He thought that he was going to be able to run it off. But if we left him on then it would only have got worse for him.
"Nani just felt his groin tighten up and he didn’t want to take any risks. Neither did we. We thought it was safer to take him off at that time."
It wasn't all bad news on the fitness front as club captain Nemanja Vidic completed his first full match in pre-season, while Robin van Persie also finished the full 90 minutes.
"[Nemanja] was probably the big thing for us, to get him through the full game," added Moyes. "Robin as well – he got 90 minutes. Robin has played in some of the other games but we wanted to make sure he had 90 minutes under his belt. So a few of them did that.
"It was a tough enough workout for us and they played some good stuff. If we had taken our chances then we would have won the game."
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