CHICAGO -- With one illegal hit late in the third period Saturday, Chicago Blackhawks defenseman Brent Seabrook may have changed the fate of two teams who believe they can win the Stanley Cup this season.

He certainly changed the fate of two players who are important to their respective Cup-contending teams.

The NHL's Department of Player Safety on Sunday suspended Seabrook three games for his illegal hit on St. Louis Blues captain David Backes at 15:09 of the third period of Game 2 of the Western Conference First Round series. The suspension came down approximately 22 hours after Seabrook's hit sent Backes to the dressing room early and gave the Blues the opportunity to tie the game.

Vladimir Tarasenko answered with a power-play goal with 6.4 seconds left in regulation. Barret Jackman then scored 5:50 into overtime to give St. Louis a 4-3 win and a 2-0 lead in the best-of-7 series.

RAMSAY: HAWKS MUST TRUST LEDDY

Losing defenseman Brent Seabrook for three games is a bigger blow for the Chicago Blackhawks than the St. Louis Blues' potentially losing center David Backes for an indeterminate amount of time, longtime NHL coach Craig Ramsay said.

Seabrook was suspended three games by the NHL's Department of Player Safety for his illegal hit on Backes with 4:51 to play in regulation of Game 2 of the Western Conference First Round series on Saturday.

Backes is questionable for Game 3 and beyond. Seabrook, who leads Chicago with four points and has played more than 60 minutes through two games, definitely won't play.

"Seabrook has scored twice already, he plays a ton, plays on the power play, is one of their top-flight defenseman playing with [Duncan] Keith and he eats up a lot of ice time," Ramsay told NHL.com. "He scores big goals. He seems to rise to the occasion. He's been really an effective player. He's a dominating player. Defensemen can play more and when they're good they can really dominate a game moreso than a forward."

Ramsay said the best way for the Blackhawks to adjust to Seabrook's loss is to put more faith in defenseman Nick Leddy, who has averaged less than 12 minutes of regulation ice time per game in the series while playing on Chicago's third defense pair with Michal Rozsival.

"Rozsival is an older guy, I don't know how much more he can play, but Leddy is a guy that skates well," Ramsay said.

Ramsay questioned why the Blackhawks don't trust Leddy to do more. He said when they did late in the third period of Game 6 of the Stanley Cup Final last year, Leddy answered by helping Chicago get back into the game.

He played only five shifts in Game 6 against the Boston Bruins, but his two best shifts came after Chicago fell behind 2-1. Leddy drew a penalty and the Blackhawks got four shots on goal over his two third-period shifts that totaled 1:48 in ice time.

"If you look back, Game 6 last year in Boston, they were losing but Leddy wasn't playing very much," Ramsay said. "They gave him more ice time in the third period and he really helped them turn the game around with his speed and with the offense that he can bring. He got the puck through Boston's neutral zone.

"He might be the guy that steps up now, gets some more ice time, and he'll give Chicago even more offense. I think he can make a big difference. I like the way he gets around the ice. He gives them more speed and maintains their ability to get their defenseman into the play."

-- Dan Rosen

"That's a real dagger," Blues defenseman Kevin Shattenkirk said of Tarasenko's game-tying goal. "When you're the guy sitting in the locker room and you see that goal go in, I've been on the bad side of it and know how it feels. We have to realize how much that goes further in the series."

Going further, the Blues might have to deal with the loss of Backes for an extended period in the Stanley Cup Playoffs. But the Blackhawks come home for Game 3 on Monday at United Center knowing they have to win four of the next five games, and they won't have one of their most important players for three of them.

Seabrook leads Chicago with four points in the series and has played the third most minutes on the team (60:58) behind defensemen Duncan Keith (69:05) and Niklas Hjalmarsson (66:03).

"You need his size, you need his presence, experience and leadership," Blackhawks coach Joel Quenneville said of Seabrook before learning about the suspension. "He's got the big shot on the point, and he's on our power play as well. Kills penalties. So he plays all important minutes."

St. Louis coach Ken Hitchcock can say the same things about Backes, but instead Sunday he had to talk about the health of the Blues captain. He didn't have much of an update.

"All I know is he's upright ... that's about it right now," Hitchcock told reporters in St. Louis. "We don't have any further information and probably won't until late [Monday].

"I know one thing, he couldn't play [Sunday]."

If Backes can't play Monday, it's possible he will be replaced in the lineup by Patrik Berglund, who hasn't played in the series because of an upper-body injury. Berglund skated Sunday; it was the second time he was on the ice in the past three days.

"I told the boys [Saturday] I can't take this anymore," Berglund said. "Hopefully, I will heal fast and be able to help them out on the ice. It's easier that way."

The Blues might also be dealing with a knee injury to second-line center Vladimir Sobotka, who stayed in the game Saturday after colliding knee-on-knee with Blackhawks forward Bryan Bickell.

"He's average right now," Hitchcock said of Sobotka.

Bickell received a minor penalty for kneeing on the play.

The Blackhawks know for sure that they won't have Seabrook for the next three games, if the series goes that far. That means Quenneville will have to use either Sheldon Brookbank or David Rundblad and possibly move other defensemen around to make up three new defense pairs.

It's a massive change for the Blackhawks because of how important Seabrook is to their entire game plan.

Seabrook plays the right side on Chicago's top defense pair, next to Keith. Approximately 25 percent of his ice time comes on special teams. He had a goal and an assist in each of the games at Scottrade Center.

Brookbank played 48 games during the regular season and has 18 games of playoff experience in his career. Rundblad played only 17 games in the regular season and has never appeared in a playoff game.

"It hurts, you know," Blackhawks forward Brandon Saad said of losing Seabrook. "He's a leader. He's a good player and he does the right things out there. But for the most part, we've got to accept the challenge and play without him. We can't use that as an excuse. They've been missing some players in Game 1, so we've just got to rise to the challenge and play for him."

The Blues said they played for Backes at the end of Game 2. Instead of focusing on retaliation for the hit, they focused on using the ensuing power play to their advantage.

The Blues insist they won't waste any time in Game 3 seeking retribution for the hit.

"You can't start running around taking guys' heads off," Blues forward Ryan Reaves said. "We've got a job to do, and I think the ultimate revenge is knocking them out and going on trying to win the Stanley Cup while they're packing up their golf clubs. I think that's going to be our first goal, but we're going to come at them."

The Blackhawks insist they're not worried about any reaction the Blues may have Monday.

"We're worried about playing our best and getting the momentum," Chicago defenseman Johnny Oduya said.

They'll have to try to play their best without one of their best players. The Blues are in the same predicament, but the blow is softened by their 2-0 series lead.

Seabrook's hit helped give it to them. It also took him out of the next three games. Did it take the Blackhawks out of the series too?

"Coming home, it's a fresh start," Saad said. "We needed to steal a game from their building and we couldn't do that in the first two, but there's still more to come."

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