Australian riders dominated Thursday's Moto X Best Trick contest at X Games 17, taking all three podium spots: Jackson "Jacko" Strong landed the first-ever competition front flip, spinning slightly off-axis on his way to winning Moto X Best Trick. Strong beat out his fellow Australians Cam Sinclair and Josh Sheehan, who took second and third, respectively. Sinclair landed a nac-nac double backflip variation and Sheehan landed his first competition double backflip.

Travis Pastrana, whose much-hyped rodeo 720 was expected to be a highlight of the competition, crashed in his first run and crashed again in a rebate run immediately afterward, putting the rest of his "Pastranathon" weekend -- which was also scheduled to include competition in Moto X Freestyle, a NASCAR debut, and X Games Rally events -- in jeopardy. Pastrana left the Staples Center with the X Games medical team and went to the hospital for X-rays.

Jacko Strong celebrating his win in Moto X Best Trick. Chris Tedesco/ESPN

Mark Monea went down hard on a no-handed front flip variation in run one, attempting to best Strong's front flip, and did not take his second run.

Strong, 19, made his X Games debut last year, finishing 16th in Moto X Freestyle. He was one of a handful of riders to have previously landed the front flip, but it had never been landed in competition before tonight. "I knew I'd landed it as soon as I left the ramp," Strong said. "It's a little bit shorter of a gap than I normally front flip at and I knew I had to huck this one hard. That's why I put the little twist in it, to make it spin a little quicker."

Sinclair followed up his gold medal-winning double backflip from last year's competition with an impressive nac-nac variation on the first flip before pulling the second one around. Double backflip variations are practically unheard of in FMX competition.

Sheehan, a last-minute addition to the X Games 17 lineup, spent the last week training at Pastrana's personal compound to learn the double backflip. Pastrana won Best Trick gold with the double backflip in 2006. Though he's an X Games rookie, Sheehan has been dominating the International Freestyle Motocross Federation events this year, and last month took third place in Spain at the fourth stop of the 2011 Red Bull X-Fighters series.

On the Aussie domination, Sinclair said, "We've all been looking up to the Americans and chasing them forever. A lot of effort paid off finally and we're pretty stoked. I'm sure there's a lot of Aussies at home watching and cheering on."

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