Howard Cheng Yue-tin proved to be the "King Of Class Five", winning the opening two races on the cellar dwellers and that was enough to see him share the day's riding honours with Brett Prebble in the Jockey Challenge.

"Whether it's a Class Two or a Class Five, it all counts the same in the championship," smiled Cheng after a smart ride to win on Smart Guy for Peter Ho Leung was followed by a remarkable performance to get home first on K-Moochi for Dennis Yip Chor-hong.

Taken to the front from barrier rise by Cheng, K-Moochi was keen in the initial stages and then didn't let up through the middle of the race on the turn from the 800m to the 400m, almost failing to take the bend at all.

Cheng had both hands on the right side of the reins at one point to stop K-Moochi from running off into the crowd. "He just doesn't have any idea how to go around the turn," said Cheng. "He was a very difficult ride and you don't often see horses do that and win."

But Cheng was able to wrestle K-Moochi for long enough to have him straighten up still in front and, once around the bend, the four-year-old gave him a good kick to hold off the challenges and get his first win at start nine.

Smart Guy had been ridden for speed in many of his first 18 starts, but had run home for his first minor placing at his previous run over 1,800m and Cheng was at pains to be even more patient this time.

"Going up to 2,000m for the first time, I needed him to relax so I just took him back to last early and he finished it off well. He got a little bit held up early in the straight but it might have even helped him.

"Still, even for a Class Five it was a bad race and I doubt he'll win another one any time soon," he said.