Bought for just $22,000, Rocketing By has upstaged two-time Group One winner Ole Kirk and top filly Dame Giselle to snare the rich Inglis Sprint at Randwick.

Starting at $26, the three-year-old won the race on his merits, bursting through the pack to down Prime Star ($16) by a half-length with Ole Kirk ($2.60 fav) doing his best work late another long head away.

Dame Giselle was also responsible for a nice return, finishing fourth.

Trainer David Pfieffer snapped up Rocketing By at the Scone sales and the son of So You Think has now banked more than $700,000 in prize money.

There could be more to come with the stable's next target the $500,00 Inglis Dash at Flemington.

Pfieffer said he came to Randwick hoping Rocketing By could be competitive but was not expecting him to beat the likes of Ole Kirk.

"It was a cracker field. We were coming here hoping to run a place and run respectably," Pfieffer said.

"There were two very, very good horses in the race but we knew we were coming here in form and targeting this race, whereas others were using this race as a stepping stone.

"Our grand plan has come off."

Rocketing By was cheered back to scale by a large and excited group of owners.

Even Pfieffer didn't know exactly how many had a stake in the horse but he was happy to celebrate a bright spot in what had been a tough week after one of the stable's riders suffered a serious injury at trackwork.

"It has been a bit of an emotional week this week so it helps a bit," he said.