The inexperienced Riccarton filly took on a hot field of three-year-olds in the Cambridge Breeders' Stakes and turned in an outstanding effort to finish runner-up to Xtravagant.
"She had to take a huge step up and it felt like a win," said Pitman, who prepares the exciting daughter of Swiss Ace with his son, Matthew.
"We were pretty hopeful she would go really well, but it was a big undertaking for such a lightly-raced horse."
First Serve had won her first two starts on her home track before trekking north and her task wasn't made any easier when the Cook Strait ferry was held up. "There was a major delay so it was a big trip for her," Pitman said.
"She's got a fantastic temperament and she's very competitive.
"She's proved how capable she is now and it's so important to get black type.
"We're going to gather our thoughts later this week and decide what to do."
Pitman was also delighted with the last-start success at Marlborough of First Serve's regular companion Montoya Star.
"They've been training mates, paddock mates and spelling mates all the way through," he said.
The High Chaparral filly broke her maiden over 1400 metres at her third start and she is expected to improve with time and over more ground.
Meanwhile, the stakes performer El Doute may resume his New Zealand career for the stable this weekend.
"We're really happy with him and he might start on Saturday at Riccarton," Pitman said.
He won four races, finished runner-up in the Listed Dunedin Guineas and fifth in the group one Levin Classic before a stint with Chris Waller in Sydney where he was successful at Rosehill.
- NZ Racing Desk