ESPN.com asked Barry Melrose to pick a player whose contribution is integral to his team's playoff success. No goalies allowed.

	For Boston's Bill Guerin, playing physical in the playoffs may be easier than scoring goals.

Montreal vs. Boston
Bruins: Bill Guerin
The Bruins can't win the Cup if their best player doesn't play like their best player, and Guerin is the B's best player. He's been great all season long, but goals are going to be much tougher for him to get in the playoffs. Guerin has to lead them offensively, he has to be physical, and he has to be clutch.

Canadiens: Yanic Perreault
Perreault has been their best, most consistent player all season long. Of course, they're hoping Saku Koivu and Donald Audette can come back and supply some offense, but it is Perreault who must get it done.

Ottawa vs. Philadelphia
Flyers: Keith Primeau
The Flyers have a ton of talent, but it is Primeau who stirs the drink in Philadelphia. Neither the scoring nor the power play has been very good for the Flyers in the past few weeks. Of course, that could all change come playoff time, but Primeau needs to play exactly the way he did in the last 10 games of the season. It is Primeau who can change the course of the game with a big hit, fight, or goal.

Senators: Daniel Alfredsson
Alfredsson is the heart and soul of this team -- he is the captain, the spokesman and the conscience. When they need a goal in the playoffs, Alfredsson has to be the guy who gets it for them.

	O'Neill

New Jersey vs. Carolina
Hurricanes: Jeff O'Neill
The Hurricanes know they're going get top notch play from Ron Francis and Rod Brind'Amour, but O'Neill is the guy who can surprise. He makes their power play go, he is a great shooter, and he needs to have a good playoffs for the Hurricanes to have a good chance.

Devils: Bobby Holik
Whenever the Devils need a big play, a big hit, or a surge of energy, it is Bobby Holik they look to. His contributions in those areas will be more important than ever this year in the playoffs.

	Sundin

N.Y. Islanders vs. Toronto
Maple Leafs: Mats Sundin
Sundin has been the Maple Leaf's best player all year long -- that can't change now that it is playoff time. To be a true leader -- you have to be one during the regular season, then you have to remain a leader during the playoffs. We'll see if Sundin is a true leader.

Islanders: Michael Peca
Peca changed the face of the Islanders the minute he arrived -- he made the whole team play harder. He'll be going up against Mats Sundin, and he will have to be awesome for the Islanders to have a chance.

Barry Melrose, a former NHL defenseman and coach, is a hockey analyst for ESPN.