Ibrox side Glasgow Rangers edged out Hearts on the weekend.
The young midfielder scored Rangers' second goal as Mark Warburton's side beat Hearts 2-0 at Ibrox on Saturday afternoon.
The 21-year-old has only netted twice from 23 appearances in all competitions this season, leading to a bit of criticism over his output.
But Garner says that the young Gers man is a "top, top player".
“Baz is only a young lad. I see him every day in training and he is a top, top player," he told the Glasgow Evening Times.
“You saw that [on Saturday] and the fans were right behind him. He can be anything he wants to be.
“What age is Barry? 21? He is not very old. Trust me, he has all the ability to go wherever he wants. Let him play his football.”
Rangers, in second, are eight points behind Premiership leaders Celtic, who have three games in hand. Given they have won 40 out of 42 points this season, the Hoops would probably win those three matches so the deficit could well be 17 points shortly.
It's been a tough return to the big time for the most part and guys like McKay symbolise the difficult transition to life in the top flight again, but he is certainly a classy player and Gers fans will hope to see a lot more evidence of it over the coming weeks and months.