When he left TD Garden with a shootout victory over Tuukka Rask and the Bruins Nov. 6, St. Louis goaltender Jaroslav Halak looked like Tim Thomas’ stiffest competition in the early-season Vezina Trophy race.

Since then, Halak has fallen a few lengths behind the obvious leader Thomas.

In his last four games, all losses (three in regulation), Halak has allowed 19 goals. Last night in a loss to Detroit, he added the ultimate insult by scoring on himself.

Halak’s numbers have ballooned to a .906 save percentage and a 2.48 goals-against average. Those stats make you wonder if the former Montreal Canadiens netminder is yearning for a return to the Eastern Conference. During his 8-1-1 start to the year, Halak beat four Eastern clubs. As Jeff Gordon of the Post-Dispatch wrote today, Halak has gone from “unbeatable to hapless.”

Meanwhile, despite allowing four goals in a wild contest at Pittsburgh last week, Thomas’ totals are still pretty gaudy. He leads the league in save percentage (.959) and shutouts (4), is second in GAA (1.37) and third in wins (10). As long as he’s still getting a slight majority of the starts over Rask, Thomas will remain a Vezina contender.

But with Halak falling from the top pack, where is Thomas’ stiffest competition coming from? With GAA leader Mathieu Garon unlikely to take the No. 1 job from Steve Mason in Columbus, he’s out. The Los Angeles Kings’ Jonathan Quick seems to have come of age these first two months of the season, and the extra competition from No. 2 (or No. 1A) rookie netminder Jonathan Bernier seems to be working as a motivational tool with the former UMass standout.

Quick is third in save percentage (.936) and GAA (1.73). Playing on a winner in LA behind a solid defensive system drawn up by head coach Terry Murray should keep Quick in the Vezina talk, unless Bernier starts to really cut into the incumbent’s playing time.

And then the irony comes in. While Halak has slumped, the man Montreal decided to keep after trading Halak has heated up. We might finally be seeing the Carey Price we’ve been told about for years. Price is fifth in GAA (2.05), tied for second in shutouts (3) and sixth in save percentage (.930). Just as important, his Habs are winning regularly and he has been a major factor with wins in five of his last six outings. That Price could be proving the Canadiens right after all this time and all the outrage over last summer’s trade of Halak is one of the great early-season stories in the NHL.

So the next five Bruins-Habs games might be about more than just maintaining a decades-long grudge between teams. They might be a goaltender-vs.-goaltender showdown for the Vezina. Thomas sat out the first meeting, and the Bruins fell short. That’s can’t happen too many more times, if the Bruins want to catch the Habs in the standings and Thomas wants to regain the season-ending hardware.

Of course, it’s still early and we might not have heard the last of Halak.