If they take care of business at home, they don't have to win again at the JLC.
London took two penalties in the first period of sudden death. Goalie Michael Houser was whistled for knocking the net off the moorings during a scrum in a controversial - and gutsy - delay of game call while Matt Rupert was caught for cross-checking.
They managed to kill them.
The Knights and IceDogs both struggled on the power play and squandered glorious opportunities.
Early in the third, London tied it right after taking a too-many-men penalty that negated a man advantage opportunity.
Facing some extended four-on-four play, London's 45-goal gunner Seth Griffith stormed past Niagara centre Ryan Strome on a defensive zone faceoff, hustled the length of the ice and converted a crafty pass from long-time linemate Vladislav Namestnikov.
Houser, named the league's most outstanding player on Wednesday, made a lunging paddle save off IceDogs veteran Alex Friesen, then foiled Freddie Hamilton with his glove in the third to force overtime.
The Knights needed both of them.
Late in the second, Niagara captain and IceDogs franchise scoring leader Andrew Agozzino whipped home a tough-angle shot on a smart feed from Friesen with 1:37 left to put the IceDogs in the lead.
Back-checking Matt Rupert couldn't break up the pass and all three IceDogs overagers - Agozzino, Friesen and David Pacan - have eight goals in these playoffs.
But Niagara couldn't protect it.
Namestnikov, the Tampa Bay first rounder, made life difficult for Niagara's defenders when he showed off his skating skills.
It was much needed. The Knights, who rode a seven-game post-season win streak into the contest, didn't display much speed early.
They fell behind in the first when former Sarnia Sting forward Brett Ritchie launched a shot from the corner that Mitchell Theoret tipped past a screened Houser.
The Knights responded when rookie Max Domi, on a 2-on-1 with back-from-injury Greg McKegg, beat two-time Canadian world junior goalie Mark Visentin on a quick shot to give the home crowd a jolt.
But the Knights weren't able to create many more odd-man rushes.
Ritchie, moved to Niagara before the trade deadline in January, established some dominance down low against the Knights defencemen in the opening game.
He's a problem for London right now.
When he owns the puck, the Knights spend precious time chasing him.
If you can't produce at least 10 quality chances in a game against Visentin, you're putting yourself in a rather precarious position.
There's a reason beyond his ability why his goals against average was under two per game (1.99) and he set the league's single-season record for shutouts (10).
Niagara IceDogs GM and head coach Marty Williamson forced London bench boss Mark Hunter to make some quick line adjustments in the opening period.
Early on, he bunched together his three oldest players - Friesen, Agozzino and Pacan. The Austin Watson and Rupert twin trio, a prime shutdown line, can only be responsible for stopping one line.
The IceDogs have some serious scoring talent up front.
There isn't much better in junior hockey than a line of Strome, who missed both regular-season games against the Knights, former Windsor Spitfire Tom Kuhnhackl and Freddie Hamilton.
Being able to follow that unit with veterans like Ritchie, Ilderton native Steve Shipley and Theoret gives the IceDogs signifcant weapons.
The clubs were content to let their so-called fourth lines battle against each other. If London's Chris Tierney, Josh Anderson and Bo Horvat can generate some offensive prowess during this series, it will make Williamson think about shortening his bench.
The goaltending battle lived up to its advance billing.
Visentin, the Phoenix Coyotes first rounder, made a tremendous blocker save as the Knights tried to crash the crease area. Houser kicked aside a dangerous pinball-style drive in the early going.
E-mail firstname.lastname@example.org, read Ryan's column or follow Ryanatlfpress on Twitter.
(Niagara leads best-of-seven championship series 1-0)
IceDogs 3, Knights 2 (2OT)
Niagara goals: Mitchell Theoret, Andrew Agozzino, Dougie Hamilton
London goals: Max Domi, Seth Griffith
Next: Game 2 is Saturday night at Jack Gatecliff Arena in St. Catharines. Game time is 7 p.m.