Toronto Maple Leafs forwards Auston Matthews and Calle Jarnkrok will not play in Thursday’s preseason game against the Montreal Canadiens.

Matthews and Jarnkrok were both getting some work in before Thursday’s practice session started. Toronto’s captain was listed with an upper-body injury but Maple Leafs head coach Craig Berube told reporters Tuesday that it wasn’t serious.

Matthews scored in Sunday’s preseason loss to the Ottawa Senators, where he centred a line featuring Mitch Marner and Matthew Knies. While the Leafs haven’t confirmed their opening night roster, it appears almost certain that Knies-Matthews-Marner will function as Toronto’s top line on opening night, while Nylander will get an extended look at centre, flanked by Domi. Matthews practiced with the game group, while Jarnkrok left after the individual session.

Jarnkrok was previously placed on a line alongside William Nylander and Max Domi, providing some all-around stability to a line that should aim to outscore opponents at will this season. The 33-year-old is working through a lower-body injury.

This is Toronto’s third preseason contest, where Easton Cowan, Max Pacioretty and Steven Lorentz will get an extended look at making the roster. Cowan is Toronto’s top prospect and has previously played alongside Pacioretty and John Tavares throughout the preseason, but has been held scoreless during the first two contests against the Senators. He was among the players at Thursday’s optional skate, including Pacioretty, Timothy Liljegren, Simon Benoit, Morgan Rielly, and both goaltenders listed for the game, Matt Murray and Anthony Stolarz. Pacioretty appears to be in the lead for one of the final roster spots, after a two-goal performance Sunday against the Senators.

Toronto will be playing its opening night defence pairings and it’ll be compelling to see how a nearly full roster functions during the preseason where process is ultimately more important than the results.