Monster Kawasaki's Billy Mackenzie suffered from arm pump on Sunday at Wodonga. Image: Alex Gobert.

Monster Energy Kawasaki’s Billy Mackenzie is confident he’ll bounce back and contend for the Pro Open championship after a difficult Rockstar Energy Drink MX Nationals weekend at Wodonga.

Mackenzie finished sixth overall with 6-5-8-6 results, his best performance coming in moto three until he crashed while running in third.

The Scotsman said it was a mixture of starts and arm pump that held him back over the weekend.

“Without a doubt, starts did me in today. Whether it was my reaction time or tyre compound choice, I don’t know but I kept getting the concrete starts wrong,” Mackenzie reflected. “Then after bad starts I just struggled on the short and tight track.

“I was getting a lot of arm pump and found it difficult to pass riders and push as had as I’d like. I couldn’t flow. For me it was a really tough weekend and I’m pretty disappointed but I’m looking forward to working super hard over the next few weeks.

“There are still many points on offer and I’m looking forward to getting back to Coolum later in the month for the final two rounds. It’s a track I did well at last year.

“I’ll bounce back from this and a few solid moto results will put me well and truly in the mix for the championship.”

Mackenzie now sits third in the championship chase, 16 points behind teammate and series leader Dean Ferris.