The United midfielder had not played since November 22 last year after being diagnosed with ulcerative colitis, a chronic inflammatory bowel condition.
The 28-year-old played the final 30 minutes in front of a packed Pittodrie, and Ferguson told MUTV: "It's been quiet progress for the boy. He joined in training a couple of weeks ago and it's one of those situations where you say: 'Let's see how he does because he has had a really difficult time in the last year'."
He went on: "Therefore, I wasn't really placing too much hope in it but let's see how he does.
"He's got to the stage now where he feels he needs a game. I let him join Scotland this week but he wanted a game so I said: 'Come to Aberdeen and join up afterwards'.
"I'll give him 20 to 25 minutes."