He loved it from the start and knew early on that the sport was for him.
The Brigden, Ont., native is 20 now and in his third year as a professional supercross racer. He's back in Canada this week to prepare for Saturday's Monster Energy AMA Supercross at Rogers Centre.
"I love having that adrenalin you get sitting on a line with 22 guys or 40 guys and being able to go out there and battle it out," he said Thursday before a practice session. "You know, jump 30 feet high and everything like that. I think it's the most freeing sport out there.
"So for me, I love it. I've done it my whole life and I wouldn't change it."
Thompson's hometown is located just outside the southwest Ontario border city of Sarnia. His four older brothers all raced at a competitive level and helped build tracks on the family farm.
"It's kind of been in the family I guess you could say for years now," he said. "We live it."
Thompson rode for fun as a youngster but as he watched his brothers start to excel, he decided to try out a race here and there. The competitive side of the sport eventually drew him in and he got serious about it.
He would learn as much as he could from his brothers — Justin, Kyle, Jay and Jeffrey — and try to apply things on his own bike.
There were never any thoughts of post-secondary education. Thompson knew that racing was for him and he was determined to get there.
"Being able to go out there every Saturday night and race in front of thousands of people and do what I love is quite incredible," he said.
In supercross, racers reach top speeds of about 65 kilometres per hour as they navigate rollers, turns and jumps while completing laps on a dirt track. Space can be at a premium so racers are constantly battling the risk-reward element.
Thompson had decent results in his first two years as a pro and caught a break late last year when a spot opened on the Rockstar Energy Racing team due to an injury. The team needed a fill-in rider and wanted Thompson for the position.
He jumped at the opportunity.
"Having factory support is beyond anything I can imagine," Thompson said. "Having the advice and the bike that everyone wants is huge. Now it's down to me just getting out there and getting the results."
Thompson has posted some top-10 finishes this season and currently sits seventh in the regional standings, an impressive position considering the depth of this year's field. However, he's still looking for that first big breakthrough performance.
The five-foot-nine 150-pound racer competes in the 250SX Class, one level below the elite 450SX Class. He'll have over two dozen friends and family in attendance this weekend.
"I feel like if anywhere, this is the place I can prove myself, that I'm worthy of being on factory equipment for years to come," he said. "So we'll see."
Thompson is aiming to finish the season strong and crack the top five in the standings. He's feeling strong physically but admits his mental game still needs work.
"I'm my biggest enemy out of anyone," he said. "Mentally I put a lot of pressure on myself and I doubt myself a lot. I don't give myself a fair chance sometimes. I look around and I'm like, 'I don't know if I'm capable of this,' when I'm perfectly capable of it. So mentally I need to start giving myself more credit.
"I think once I start doing that and believing in myself that I can go out there and race with the best and be the best and everything like that, I think everything else will come."
Adam Cianciarulo leads the 250SX Class standings while fellow American Ryan Villopoto is first in the 450SX Class standings. Villopoto is the two-time defending champion here and has won three of the last four Toronto races overall.
About 50,000 fans are expected to attend Saturday's event. It's the lone Canadian stop on the circuit.
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