Which leaves a bigger hole -- a 6-foot-4 Swede or a 6-foot-9 Slovak?

If you're talking about sheer crater size, surely no NHLer would create a more extensive impact zone than Ottawa Senator Zdeno Chara.

But if it's the influence a player has on the Stanley Cup playoffs, it would be Mats Sundin.

Or would it?

That's part of the puzzle that will finally come together tonight when the Maple Leafs and Senators finish off their best-of-seven Eastern Conference semifinal series, the third consecutive Battle of Ontario and without question the most heated so far.

Blood and broken bones have had much to do with the competition so far, perhaps to an absurd level. After Tie Domi suffered a deep laceration in his forehead after being hit from behind by Sens defenseman Ricard Persson in Game 6 Sunday night in Ottawa, an incident that opened the door to a Leafs comeback and ultimately a victory, there were snide suggestions yesterday from within the Ottawa dressing room that Domi might have somehow taken a dive to draw the major penalty.

What's next? Allegations of a foreign object? Dropping a cage over the rink when Game 7 begins tonight?

Such are the tensions that have been created in this series between two Ontario cities, one that serves as Canada's much despised capital city and tries to fashion itself as the little engine that could but recently needed a cash handout from the NHL to pay it's bills, the other a self-absorbed burg known as Hogtown that hasn't won a Stanley Cup in 35 years but still fancies itself as the center of the hockey universe.

Game 7 tonight, then, will resolve everything and resolve nothing in a sports rivalry that seems destined to grow.

Part of winning this game will be the ability of each team to compensate for the absence of key athletes due to injury, and that's where the Sundin/Chara comparison comes in.

Sundin has been lost for 10 of the Leafs' 13 playoff games this spring, unavailable since Game 3 of the opening round against the New York Islanders because of a broken wrist.

Since then, the Leafs have gone 5-5 despite the fact that their captain's injury has been accompanied by health woes of five regulars and some of their replacements, as well.

The Sens, meanwhile, were remarkably healthy for the entire first round against Philly and the first four games against the Leafs. Then No. 3 center Mike Fisher went down with a knee injury early in Game 5 followed by a similar knee problem suffered by Chara in the final minutes.

In Game 6, a 4-3 Leafs victory, Chara was missed desperately on the Senators blue line, and not only because his replacement, Persson, took the major for hitting Domi from behind that allowed the Leafs to turn an early 2-0 deficit into a 2-2 tie.

But while Sundin is probably one of the top five players in the world and the Leafs have many more players lost to injury at this point, Ottawa may find it more difficult to replace their crease-clearing blueliner.

That, of course, is often the problem for small-market teams. They can often ice a team that's more than competitive with large payroll franchises, but when injuries strike they don't have the financial depth to carry quality backups.

The Leafs, for example, have seen Alyn McCauley rise to the occasion and deliver 13 points in 13 games while standing in for Sundin as the No. 1 center. The Leafs have used multiple callups from their St. John's farm club, even players they tried to dump on waivers earlier in the season like defenseman Anders Eriksson, and managed to stay alive.

The Sens may have more depth than ever before, but without Chara and Fisher for Game 6 they were a much different club.

With no Chara, Gary Roberts ran wild in the Ottawa zone, and Alexander Mogilny scored his first goal of the series. Fisher, meanwhile, had helped give the Sens a viable third line, but without him they managed only two shots on the Toronto net in Game 6 after Mogilny had given the Leafs a 4-3 lead in the fifth minute of the third period.

The Chara-Sundin comparison, meanwhile, might be even more intriguing if Sundin is able to make a dramatic return tonight, although that looms as a very remote scenario.

The Leafs center has been practicing for several days and is back to shooting the puck, but the consensus is still that he won't be back unless the Leafs make it to the conference finals.

"If I can play, if I'm cleared to play, I'm going to play. But I'll have to see what the doctors have to say," said Sundin after practice Monday.

As much as it will be important for the Sens to fill capably for Chara, even more important will be Ottawa's ability to overcome some seriously negative mojo about the playoffs in general and their history against the Leafs specifically.

The franchise lost the only other Game 7 in which it participated, in 1997 against Buffalo. The Sens lost to the Leafs in the first round of the 2000 playoffs, then were swept by them last spring despite being heavily favored going into the series.

This year, they figured to have the upper hand against a badly banged up Leafs team that needed seven games to subdue the Islanders but haven't been able to close the deal with authority.

With a 2-1 series lead and Game 4 on home ice, the Senators lost. They then won Game 5 in Toronto, with Daniel Alfredsson executing a brutal hit on Darcy Tucker that created the winning goal and eliminated Tucker from the series, but once more couldn't follow up with a victory on home ice despite their early lead.

In five of the six games played, the Sens have scored first, yet they find themselves facing elimination tonight. Part of that has been due to the awesome performance of Roberts, who has scored or organized nine of the past 10 Toronto goals. It also has much to do with an Ottawa team that has clearly matured, but still may not have the internal combustion to deal with their nemesis or inner demons.

"We're as disappointed as the fans," said defenseman Chris Phillips. "We could have ended this series, but we have a Game 7 instead."

The Leafs, meanwhile, have a battle-hardened core of veterans, many of whom have been in this situations multiple times. Jyrki Lumme, who may be re-activated for this game from the injury list, has played in six Game 7s, while Shayne Corson, Gary Roberts and Robert Reichel and Mogilny have skated in five each.

Leading all Leafs, however, is netminder Curtis Joseph, who has been in seven such matches, winning three, losing three and mopping up for a teammate in the other with no decision. In 1997 and '98, Joseph was the hero for the Oilers in Game 7 playoff upsets over Dallas and Colorado, respectively, with his miraculous save on Dallas forward Joe Nieuwendyk in overtime of Game 7 still a cherished memory in Edmonton.

Ottawa goalie Patrick Lalime, by comparison, has never played in a Game 7 at the NHL level. Only four Senators, a list that includes Alfredsson, Radek Bonk, Wade Redden and Chris Phillips, played in the club's last Game 7 match five years ago against the Sabres.

So it may not be just about whether Sundin or Chara leaves a bigger hole. It may be more about whether the Sens can finally heal the hole in their soul.

Damien Cox is a columnist for the Toronto Star.