Australian cyclist Michael Matthews has dedicated his third career victory at the Grand Prix Cycliste de Québec to his grandmother, who died during the week.

Matthews prevailed in a chaotic sprint at the end of the 201.6km race, launching from a long way out to hold off the chasing pack, which included Tour de France winner Tadej Pogačar and this year's green jersey winner, Binian Girmay, who finished second.

It is the Canberran's third victory in the race, having previously won in 2018 and 2019.

"I knew it was a hard day so no one had a real kick in their sprint, so when the bunch all moved to the left I saw an opportunity to open up my sprint on the right," Matthews said.

"No one probably expected someone to go from that early.

"I knew I didn't have the peak power today but I knew I had a really long sprint and I had the power to do a 15-, 20-second sprint today."

Matthews has endured a frustrating season, coming no higher than 10th in any stage during the Tour de France and finishing 15th at the Olympic Games in Paris.

That came after a promising start to the season for the 33-year-old, when he won the Gran Premio Castellón and finished second at Milan-SanRemo.

He also came close to victory at the Ronde van Vlaanderen (Tour of Flanders) but was controversially relegated after being judged to have deviated in his sprint.

The Team Jayco-AlUla rider admitted that relegation derailed his season.

"I had a really good start to the year, but since Flanders and my disqualification in that sprint, my head rolled off a little bit, honestly.

"With the Tour de France and the Olympics, I was trying to make up for that unfortunate relegation.

"To bounce back here, with the lead up to the world championships … it's incredible.

"It's something we've been working for as a team. Since the Olympics until now, I've worked so hard, so full credit to my team, my family.

"My grandmother passed away last Wednesday, her funeral was this Wednesday in Canberra so this victory is for her."

Matthews will now turn his attention to the Grand Prix Cycliste de Montréal on Sunday, and then the World Championships in Switzerland at the end of September.

Matthews has finished on the road race podium at the world championships twice, winning bronze in Wollongong in 2022 and Bergen in 2017.

The road race at the World championships in Zurich takes place on September 29.