Pogba joined Manchester United from Juventus in a world record deal last summer.
But the France international is yet to find his best form at Old Trafford, and he was heavily criticised for his performance in Saturday's 1-1 draw with Bournemouth.
However, United legend Giggs believes criticism of the midfielder is unfair.
Ryan Giggs has leapt to the defence of Manchester United star Paul Pogba
"I have never seen a 23-year-old midfield player dominate games for a whole season," he said.
"So, the £90 million that they paid is what obviously people focus on and what people talk about.
"He will become a brilliant midfielder; there is no doubt in that.
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Manchester United star Paul Pogba has been criticised for his recent performances
"I think he scored seven or eight goals, again, not many midfielders at 23 will do that.
“But because he cost so much, he is compared with that price tag when actually, he has done okay this season.
"Okay, not brilliant but not really bad.
“So yeah, I think a lot people should cut him a bit of slack."