TORONTO -- Nazem Kadri was actually doing a decent job of keeping his cool.

There was the on-ice wrestling match that ended with the Toronto Maple Leafs centre getting punched in the face by Boston Bruins winger Jake DeBrusk.

Kadri was then felled by a knee-on-knee hit -- again from DeBrusk -- that resulted in him limping off before he eventually returned to the fray.

But a third incident in the Bruins' 4-1 victory inside a deafening TD Garden on Saturday night that knotted their first-round playoff series 1-1 saw Kadri snap in yet another moment of post-season madness.

After watching DeBrusk chase down Toronto's Patrick Marleau and slam the 39-year-old into the curved glass at the end of the bench, Kadri unleashed a vicious cross-check to DeBrusk's face, resulting in a major penalty and game misconduct.

The NHL's department of public safety tweeted it had offered Kadri an in-person hearing, giving the league the option to suspend him for more than five games.

That session is set for Monday afternoon in New York, just hours before the Leafs and Bruins are scheduled to renew hostilities in Game 3 at Scotiabank Arena.

"You have to play real hard and look after yourself, but you can't cross the line," Toronto head coach Mike Babcock said on a conference call with reporters Sunday. "Any time you do, you leave decisions in someone else's hands and it's not within your control.

"In anything in life, you want to be in control and you've got to own everything. You've got to own your play, you've got to own your discipline, you've got to own what's going on for you. In the end, Naz has someone else making a decision whether he's playing or not."

Kadri, who was not made available to the media Saturday, was banned three games for boarding on Bruins winger Tommy Wingels in the opener of last year's seven-game defeat to Boston.

The 28-year-old has been suspended four times for a total of 14 games in his career, including that trio playoff contests. He's also been fined on three occasions -- twice for diving/embellishment and once for an inappropriate throat-slashing gesture -- making this the eighth instance where he's been tapped on the shoulder by the NHL to explain himself.

And all four of Kadri's previous suspensions also involved him targeting an opponent's head, a no-no in today's game.

Babcock's options as replacements for his third-line centre include Marleau and William Nylander, but neither scenario is ideal.

"It's disappointing for Naz, it's disappointing for our team," Babcock said. "We've just got to move on."

The Leafs will be looking to rebound Monday following a physical and emotional Game 2 that saw the Bruins come out swinging -- literally and figuratively -- following a sub-par performance in Toronto's emphatic 4-1 victory in the opener.

Boston hit everything in sight, jumping out to 3-0 lead in the second period before Kadri scored midway through the third, about four minutes before his cross-check on DeBrusk.

"They had a push and we weren't really ready for it," Leafs defenceman Jake Muzzin said after the game in the visitors locker-room at TD Garden. "It's our turn to come out with a push."

While the Leafs will be in tough minus Kadri, one of the team's grittier options at a time of year when the games get harder and officials tend to let more go, they're also in better shape than at this time 12 months ago.

Boston outscored Toronto 12-4 in winning the first two games of the 2018 series, with Kadri driving the head of a vulnerable Wingels into the boards late in the opener after he hit Mitch Marner up high.

This time around, the Leafs have Auston Matthews and John Tavares down the middle ahead of Kadri. Last spring, Tomas Plekanec and Dominic Moore -- both no longer NHL players -- lined up as options behind Matthews.

Toronto got on top of Boston's defence in Game 1 with its speed. It also kept the Bruins No. 1 line of Brad Marchand, Patrice Bergeron and David Pastrnak off the scoresheet at five-on-five.

But the tables turned Saturday as the home side came out flying before a raucous crowd as the Bruins pressed hard in the offensive zone and took away the Leafs' time and space.

"Their level of urgency, as much as we talked about it and prepared for it, we didn't match it," Babcock said. "We made a couple of key mistakes early. We've got to be much better, we understand that, we know that.

"Now we've got to do something about that."

But almost certainly without Kadri -- and in all likelihood for an extended period of time.