Giro d'Italia winner Dumoulin was second at the GP Quebec and sixth at the GP Montreal on his only previous appearances at the two races in 2013. The 26-year-old is using the races to tune up for the World Championships later this month in Bergen Norway and aiming for a result. Dumoulin hasn't raced since winning the BinckBank Tour in August.
Matthews, who has been confirmed as the protected rider for Australia at Worlds, was second at Quebec in 2015, fifth last year and also finished fourth at Montreal in 2016. Since winning two stages of the Tour de France and points classification in July, Matthews has finished third at RideLondon and fifth at Bretagne Classic.
Matthews will be the main rider in both races for the team with Dumoulin and Simon Geschke also to play key roles in the GP Québec.
"Québec offers a challenging course straight through the city centre, with a decimated bunch traditionally sprinting to the victory," coach coach Aike Visbeek said. "Our goal is to sprint with Michael and have 3-4 riders with him inside the finishing laps of the race. We have Simon and Tom who have previously taken some strong results here and we expect them to play an important support role in the finale."
For Montreal, two days after Québec on September 10, the team can also count on Nikias Arndt for the 205.7km race as Visbeek added.
"In Montreal Michael will be our designated sprinter. After some good preparations for this part of the season at altitude, he is in good shape and feeling prepared for a good race," Visbeek said. "It is typically an open race where a decisive break can go for the victory but also a bunch sprint is still an option. We have a strong team to support our goals with guys like Simon, Tom and Nikias who will play a crucial part in the final."
With 500 WorldTour points on offer for the winner at both races, Dumoulin and Matthews can both move up the rankings and consolidate Sunweb's fourth place position in the team standings.
Team Sunweb for Grand Prix Cycliste de Quebec and Grand Prix Cycliste de Montreal: Nikias Arndt (Ger), Tom Dumoulin (Ned), Simon Geschke (Ger), Michael Matthews (Aus), Georg Preidler (Aut), Mike Teunissen (Ned), Albert Timmer (Ned) and Zico Waeytens (Bel).
Click here to subscribe to the Cyclingnews podcast.