Drew Stafford is expected to miss two games with a mild groin injury, leaving the Buffalo Sabres down yet another top-line forward in their bid to climb back into playoff contention.

Coach Lindy Ruff listed Stafford as day to day Wednesday, a day after he was hurt in a 2-1 overtime win over Montreal. Stafford played only two shifts before leaving in the first period.

The initial prognosis was good news of sorts for Ruff. His team, after all, is already minus center Derek Roy, who will miss the rest of the season after tearing his left quadriceps tendon last month.

"It is a relief," Ruff said. "He's walking fine and his strength is pretty good. So, all that bodes well for coming back quickly."

Ruff called it doubtful that Stafford will play at Boston on Thursday or the following day, when the Sabres host the New York Islanders. There's a possibility Stafford could return for Buffalo's game at Long Island on Sunday.

Stafford has been one of the Sabres top scoring threats in helping the team go on a 6-2-1 run in its past nine. He ranks second on the team with 15 goals, and has scored five — including two game-winners — in the past eight games.

The win over Montreal allowed the Sabres to even their overall record at 20-20-5 and also even their home record at 11-11-1, a significant turnaround for a team that opened the season going 0-6-1 at Buffalo.

With 45 points, the Sabres, entering Wednesday's action, were tied with Florida for 10th place in the Eastern Conference standings, and eight points behind Atlanta for the eighth and final playoff spot.

But as good as the run has been, offense remains a question mark for Buffalo. With 123 goals, the Sabres rank 20th in the NHL.

Though Roy was hurt on Dec. 23, his 35 points (10 goals, 25 assists) had led the team until Thomas Vanek took over top spot with two assists against the Canadiens. He has 37 points (17 goals, 20 assists).

Stafford's injury led to more line-juggling in practice. Ruff had Jochen Hecht centering Vanek and Jason Pominville on the team's top line, followed by Tim Connolly centering Tyler Ennis and Cody McCormick.

The Sabres beat Montreal by playing a gritty style, led by forward Nathan Gerbe, who had several solid scoring chances and drew the ire of Canadiens forward Scott Gomez.

The two received minor roughing penalties following a post-whistle scuffle in the third period. And Gomez was serving a penalty for high-sticking Gerbe, when Pominville scored the decisive goal 1:09 into overtime.

"I get under peoples' skin. That's kind of the nature of my game," Gerbe said. "You've got to do something every night to help your team win."

To fill Stafford's spot, the Sabres are expected to promote a player from their American Hockey League affiliate in Portland, Maine. The candidates include Luke Adam, who was demoted a day earlier, as well as Marc-Andre Gragnani, Matt Ellis and Paul Byron, who has yet to play an NHL game.