Photo by Jorge Lemus/NurPhoto via Getty ImagesTrevor Immelman has suggested that he was so impressed by Michael Thorbjornsen hitting all but one of the greens in regulation during the final round of the Rocket Classic on his way to securing his first PGA Tour victory. Thorbjornsen almost seemed to sneak up on those leading the way for the majority of the week at Detroit Golf Club.The 24-year-old went into the final round in Michigan in a tie for seventh. And there was little indication of the fireworks to come when he reached the turn on Sunday at two under par for the day.However, Thorbjornsen made five birdies on the back nine to win by two over Xander Schauffele.Trevor Immelman lauds Michael Thorbjornsen after his Rocket Classic victoryThe youngster was second in the field for strokes gained approach on Sunday, as he gained more than 3.4 shots.And speaking on CBS Sports after the tournament had concluded, Trevor Immelman outlined just how impressed he was by Thorbjornsens display during the final round.Photo by Jorge Lemus/NurPhoto via Getty ImagesJust such brilliant play on the second nine in particular, just amazing striking of the ball. And then going and taking advantage of that by making good putts. You think about 14, a great up and down on the par five. 15, the par three, he flags it, converts that. And then the last hole, what a way to finish when your nerves are jangling, youre trying to get your first win out here on the PGA Tour, and to stripe two shots down the middle of the fairway, and then roll it in from just under 30 feet was really remarkable, he said.To be able to come back in 30 and hit 17 of the 18 greens in regulation in these blustery conditions was quite special, I must say, it was a joy to watch.Xander Schauffeles season assessed as he finishes second in DetroitThere was an interesting similarity between the Rocket Classic and the 3M Open the previous week.On that occasion, Jackson Koivun finished ahead of Scottie Scheffler to secure his maiden PGA Tour victory.And in Detroit, Xander Schauffele was the heavyweight name who finished second, with the two-time major champion ending up two shots adrift of Thorbjornsen.It was Schauffeles first top five since the Valspar Championship in March. And Immelman suggested that he is likely to have mixed feelings about his finish at Detroit Golf Club.I think if you asked him and he was completely honest, I think hes a little disappointed so far in what hes produced this season. There have been a number of consistent performances, particularly in the majors, hes been there or thereabouts in those big tournaments, he said.This week, I thought he was going to win today, specifically when he took the lead after the great birdie on the ninth. You thought once he got his nose in front, he was just going to go ahead and keep his foot on the gas.But Thorbjornsen had other ideas, and to be able to make all of those birdies, five of them on the back side, hes 10 under for his last 28 holes with no bogeys, that was such great golf to watch. Im sure Xander, whilst being a little disappointed and feeling like he maybe let this one slip, hell tip his cap to the youngster and say, man, that was maybe a little too good.It is alarming that Schauffele has not won an event in the regular season since The Open Championship back in 2024, with his most recent win coming at last years Baycurrent Classic.He may take some positives from the fact that he is still 11th in the FedEx Cup standings. But clearly, it is taking Schauffele considerably longer than anyone would have expected to rediscover his very best form.