After being dumped from a horse before the opening race at Moonee Valley, Dwayne Dunn has ridden through pain to post a win on Ameristralia in the final event.

Dunn was dumped off Malaise in the mounting yard before the opening race and said he landed flat on his back.

"It went up in the air and flipped me and I lost my balance and just flopped on my back," he said.

"I didn't even get a chance to get my arms down. It took the wind out of me."

He was passed fit and rode Malaise to second and continued to ride through the meeting but said he had considered standing down through the day.

"I didn't think I was going too well. I was in a bit of trouble I reckon," he said.

But he said with the adrenaline he got through the meeting.

"I thought about standing down but I had her (Ameristralia) in the last and I thought my other rides were good," Dunn said.

"As it turned out I had three seconds and a winner.

"It will be interesting to see how I wake up tomorrow morning.

"I'll be sore tomorrow. I'm supposed to go around on Monday but we'll see what happens. I'll speak to (Racing Victoria doctor) Gary Zimmerman."

The Hawkes Racing-trained Ameristralia took out the Jacob Schweppe Handicap by a neck.

Dunn has been joined at the top of the Melbourne jockeys' premiership by Craig Williams who rode a double at Moonee Valley on Gratwick and Domino Vitale.