TORONTO — Concern gripped Morgan Rielly when his right leg locked with Buffalo Sabres‘ winger William Carrier on Tuesday night and bent in an awkward direction.

However scary the play looked and felt, both the 22-year-old and the Maple Leafs appear to have dodged a serious bullet. Toronto’s No. 1 defenceman is listed as day-to-day wilt a lower-body ailment, though he’s set to miss his first NHL game to injury when the Leafs host the New York Rangers on Thursday night.

Leafs coach Mike Babcock was unsure if Rielly would be back in time to face the Ottawa Senators on Saturday, but hinted at a short-term absence regardless.

"I’m happy I’m walking around and everything and feeling better than I was yesterday," said Rielly, in good spirits, on Wednesday afternoon.

Jake Gardiner, who piled up a career-high of more than 29 minutes against the Sabres, will play alongside rookie Nikita Zaitsev on the team’s top pair. Gardiner’s time will certainly increase from the 20 or so minutes he was averaging before the 4-3 win on Tuesday night, Toronto’s 10th victory in its last 13 games.

The 26-year-old Gardiner is in midst of his finest NHL season, on pace for a career-high 43 points while again posting strong puck possession numbers (53.5 per cent) which rank among the league’s best on defence. The Leafs garner about 56 per cent of even-strength scoring chances when he’s on the ice, also one of the top marks at the position league-wide.

Like Rielly, Gardiner is an easy skater and effective puck mover, his stick-work and positioning helping to limit the time he spends defending.

Gardiner finished at 60 per cent possession against Buffalo despite the increased workload.

"When he (does have to play defence) he’s skating well and he’s using his stick well and he’s able to break plays up and get the puck back," said Connor Carrick, his most frequent defensive partner this season. "His puck skills are good so he’s (always) moving forward again. It’s kind of rinse and repeat."

Babcock has increasingly employed Gardiner against difficult competition this season, if not quite the top lines that Rielly contends with.

Gardiner will get his first taste of those duties versus the Rangers’ top trio of Chris Kreider, Derek Stepan and Mats Zuccarello, responsibilities he appears ready to handle.

"Nowadays it seems like a lot of teams have two or three lines that are pretty high-end anyways," Gardiner said. "But yeah facing guys like (Sidney) Crosby it’s going to be a bit of a change."

Even if it’s just a short-term absence, Rielly’s loss will be felt.

He not only plays the biggest and most challenging minutes for the Leafs (around 23 per-game), but manages them effectively. Rielly ranks among the top-30 NHL defencemen with 14 even-strength points this season despite starting less than 50 per cent of his shifts in the offensive zone. He’s also above par on the puck possession side of things, and the Leafs generate the majority of even-strength scoring chances when he’s on the ice.

Only Gardiner comes close in his ability on the Toronto defence to move the puck out of the defensive zone.

Rielly has also killed penalties relatively effectively in a secondary role, a duty likely to fall to Gardiner.

"We’re on him lots about his defensive detail just because we think he can get to another level as a player yet," Babcock said of Gardiner.

Rielly thought he might be able to continue playing after the collision with Carrier, but in his one shift afterward the B.C. native knew things weren’t right and retreated to the dressing room with team doctors apparently shutting him down for the night.

He said the medical staff had a "pretty good idea of what’s going on", though both he and the team declined to provide any further details on the injury.

The Leafs have been lucky to avoid injuries to key contributors through the first half. Tyler Bozak was the lone such player to sit out and he missed only three games in December.

Babcock was wary of the ripple effect Rielly’s injury might have, namely fewer players (Gardiner and Zaitsev in all likelihood) playing bigger minutes and then risking injury themselves.

The Leafs lineup will be weakened regardless without Rielly, with Gardiner rising in the lineup and the veteran pair of Matt Hunwick and Roman Polak stepping into second-pair responsibilities. Hunwick and Polak carry a weak 45-per-cent possession mark when on the ice together this season.

Frankie Corrado will also get a rare chance to play, joining Carrick on a prospective third pair. Corrado has played in only one game all season, recently returning from a conditioning stint with the Toronto Marlies.

"Next man up right," Babcock said. "Someone else gets an opportunity. We’re going to find out who wants to play more right now."