A gelding operation and a drop in grade has allowed Godolphin galloper Tarquin return to winning form at Mornington.

Tarquin was gelded after two starts in Sydney during February and returned with a fast-finishing win in the Mornington Guineas on Saturday.

Ridden by James Winks, Tarquin ($8) scored a short neck win over Lahqa ($13) with Get The Dukes Out ($7) three quarters of a length away third.

Tarquin won at his first two starts as a two-year-old and took on Group One company during last year's Sydney autumn carnival.

"His form early doors was outstanding against Pride Of Dubai, Pasadena Girl and the like and he's had one of the major gear changes a horse can have," Winks said.

Winks was able to ride Tarquin quietly early in the race before moving into contention approaching the home turn.

"I spoke to John this morning and he said to ride him conservatively early which is the way he races best," Winks said.

"I was able to get a nice run into the race without having to do too much work on him and he was very strong late in the race."