James Millman's last ride was a winning one as Ishi broke her maiden tag under the jockey at Lingfield.
The 5/2 chance, trained by his father Rod, saved ground as she took the shortest route around the home turn and kept on strongly for his rider's urgings in the final stages as she held off the challenge of Island Express by a length and a quarter.
Millman, who partnered 137 winners in a riding career spanning nine years, announced his decision to quit on social media network Twitter, where he has developed a popular following for his honest insights into the less-glamorous side of a jockey's life.
"It's a perfect ending, it means a lot to go out on a winner," said the winning rider, who now plans to return to college to study law.
"She's been quite nervous before but we put the blinkers to help her concentrate a bit. I had my first ride here and it's great to sign off here in this way."
Millman senior told At The Races of his pride in his son's achievements as a rider.
"It's sad but he's going off to do other things and I'm sure he will make a success of them too," he said. "James has done a lot of the work on this filly. He's been a really big part of it all as assistant trainer so I'll do have to work even harder from now on!"