Bonner was impressed with the performance of McKay for Rangers against Old Firm rivals Celtic at Ibrox on Saturday afternoon.
The 22-year-old winger started the Scottish Premiership match and played for the entire 90 minutes.
Celtic legend Bonner was following the Old Firm game, and he was impressed with the performance of the Scotland international.
“I thought Barrie McKay was different class for Rangers,” Bonner told BBC Sportsound (14:42). “He was the main guy.”
Over the course of the 90 minutes at Ibrox on Saturday afternoon, hosts Rangers had 50% of the possession, took 10 shots of which six were on target, and earned four corners, according to BBC Sport.
Visitors Celtic had 50% of the possession, took 23 shots of which 10 were on target, and earned 11 corners, according to BBC Sport.
Brendan Rodgers’s side are at the top of the Scottish Premiership table at the moment with 58 points from 20 matches, 19 points clear of Rangers, who have played a game more.
The Hoops look set to win the Scottish Premiership title this season, while Rangers should be aiming for the runners-up spot.