The former Celtic goalkeeper senses the Ibrox players have responded to the Dutchman’s tactical tweaks, resulting in success in Europe and improved performances.
His alterations have also lifted a team ailing from Steven Gerrard’s departure and their Premier Sports Cup exit to Hibs, on to new heights, according to Bonner.
"During games he has been able to be very adaptable. He has changed systems around and the players have responded to that. That’s not an easy job to do halfway through a season and I think he has done that remarkably well and has got the results in Europe.
"He’s played three the back at times, moved John Lundstram [into defence], he’s played 4-3-3 and changed it round. He’s changed players around also and got them all almost at a level they didn’t think they could get to considering where they were when Steven Gerrard left,” Bonner praised on BBC Sportsound.
His fellow pundit Neil McCann agreed and believes Rangers have developed a tough mentality and were able to call upon those reserves to fightback from a goal behind during the 1-1 Old Firm draw at Celtic Park on Sunday.
"I think Giovanni van Bronckhorst has done a brilliant job,” he said. “He’ll be judged by his trophies. He’s got to the cup final, he’s still in with a shout against Leipzig, he’s taken this team today and made some really good tactical substitutions in this side and I think he has really instilled something into this Rangers side that maybe they lacked in those draws [against Ross County, Motherwell and Aberdeen earlier in the season].
“I think suddenly this is a side that has got real, proper character and it will serve them well on Thursday night and in the Scottish Cup final against Hearts.
On their Old Firm display he added: “I thought they were exceptional; digging in, reserves, character, grind, grit, determination, a will to win and not to give up – these are all really good hall-marks.”