"I'm sure the decision Kieran had to make was a tough one because he wants first team football," Keane told MUTV.
"But one or two of us spoke to him and told him he'd get his chance [at United].
"Fortunately injuries to other players have led to that and I think he's looked sharp all season.
"Phil Bardsley is another who has come in and done well.
"When injuries occur the young players will get an opportunity; I just hope they take their opportunity and enjoy it."