Keane, out since last summer with a knee injury, scored in the U21's win against Bolton Wanderers.
"It was really enjoyable just to get back on the pitch with the lads," Keane told MUTV. "It wasn't so much about the performance but just going out and enjoying myself.
"It's been frustrating for the past year but I'm putting all that behind me now and there's finally light at the end of the tunnel. I enjoyed it.
"It was nice to get back to scoring ways."
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