The all-the-way win of Majestic Duke at Flemington has helped ease the pain of co-trainers Terry and Katrina O'Sullivan losing one of their best horses to injury.

The O'Sullivans had to put smart three-year-old Golden Oldies on the long-term injury list during the week.

A Flemington winner on June 13 over 2000m, Golden Oldies strained a tendon on Tuesday and will be out for 12 months.

"It was a bit of a blow to the camp," Terry O'Sullivan said.

"This bloke (Majestic Duke) is doing a great job but that's part of this job, patching them up and moving on."

Leading under Dean Yendall, Majestic Duke ($7.50) won the David Bourke Provincial Plate on Saturday.

He defeated Baron Archer ($6.50) by 1-1/4 lengths with Rock `N' Gold ($14) a half-length away third.

"I was happy when he flew the barriers," O'Sullivan said.

"He gave a big kick on the corner, but halfway up the straight you always worry at Flemington that something's going to get over the top of you.

"But he did hold them off very well."