Jockey Jeff Penza’s hard work for the Chris Waller stable has been rewarded with a stakes win.

Lightly raced filly Summer Flame has landed a boilover win in the Listed Denise's Joy Stakes at Scone and picked up some valuable black-type for owners Rosemont Stud along the way.

Sent out a $61 chance, the three-year-old was making her NSW debut after three starts in Victoria which had yielded a midweek metropolitan win and two minor placings.

But she made the transition to stakes company seamlessly, surging to the front in the straight and holding on to defeat $4.60 equal favourites Gerringong and Thames in a tight finish where less than a length separated the first six fillies across the line.

Summer Flame had led or raced on top of the speed in her previous starts but Charlie Duckworth, representing winning trainer Chris Waller, said they instructed jockey Jeff Penza to take a slightly more conservative approach for Saturday's 1100m assignment in which he took a trail.

"She is a filly who is a bit highly strung so we asked Jeff to look after her and just basically work with her and try to be as economical as he can with her," Duckworth said.

"She was a massive price but she came up from Melbourne where she raced for us last preparation with a bit of a wrap on her.

"She has performed well in all three starts down there. It's obviously a big step up into Listed grade but she was a slow developing type, which the Written Tycoons can be, and she has taken it in her stride."

Duckworth also praised the effort of Penza, who was at Rosehill on Saturday morning riding work for the stable before making the three-hour long trek to Scone.

"Jeff was actually riding trackwork for us this morning so he has put in the hard yards recently and it's great for him to get a reward like this," Duckworth said.

"Rosemont will be absolutely delighted. Where she goes from here, Chris can work that one out, but very happy, we will take it for today."

Penza admitted he was surprised by how well Summer Flame travelled in the run having expected her to find the step up to stakes company more challenging.

"She travelled really nicely and she started to travel better the further we went into the race," Penza said.

"By the time we straightened up I was looking for somewhere to go.

"She is on her way up, I think."