Doubt existed until the last minute over whether well-bred filly Ms Funovits would make her debut in the Better Beyond Plate at Flemington on Saturday - and the result of the race was similarly problematic until the last couple of strides.

Trainer John Sadler said he'd not had any concerns over the filly's fitness or ability, only that she might not be suited to a hectic 1000m race.

"She's probably not bred to be up and about in these races at this time of the year, but she had done so well that she deserved to run," Sadler said.

Ms Funovits, a half-sister by Reset to the talented galloper Chase The Rainbow, cost her owners $230,000 at last year's Inglis Premier sale, going to the bid of Sadler's racing manager Troy Corstens.

"Troy's become an outstanding judge of a yearling, but I don't think he picked her to be a two-year-old," Sadler said.

"Right up the death he was texting me asking if I was sure I wanted to run her."

Despite all the concerns, Ms Funovits ($7) went straight to the front, fighting back after being headed to beat the favourite Thermal Current ($3.80) by a head.

Mount Zero ($4.20), who got to the lead at the 200m, weakened to finish third, a further half-head away.

For jockey Glen Boss the win extended his lead in the Melbourne jockey's championship to 12 and justified a decision to ride at Flemington rather than chase mounts at the Magic Millions meeting.

"John Sadler told me he had a good two-year-old for me to ride," Boss said.

"His horses are here because they can win."