They’re hoping he’s the last.

“David Krejci is not around the team,’’ said coach Claude Julien, referring to the quarantine (3-5 days, according to general manager Peter Chiarelli) placed on the center. “Hopefully that’s where it will stop. But there’s no guarantee. We’re all vulnerable to it. We just have to deal with it the best we can.’’

Krejci joins a handful of NHLers who have been diagnosed with H1N1. Others include Edmonton’s Ladislav Smid, Colorado’s Peter Budaj, Washington’s Quintin Laing, and the Islanders’ Doug Weight.

“Kind of took me by surprise, like everyone else,’’ said Blake Wheeler, Krejci’s left wing Tuesday. “I guess that’s the way the world is today. You’ve got to be careful. Obviously we wish him the best and a speedy recovery.’’

The Red Wings were having their own issues with illness; Brian Rafalski and Jonathan Ericsson missed the game because of flu-like symptoms. The Wings were in Edmonton last Thursday, where Smid had been diagnosed with H1N1. Last Saturday, Smid, having recovered from his bout with H1N1, was in the lineup for the Oilers’ 2-0 loss to the Bruins at TD Garden.

The Bruins have not received the vaccine for the H1N1 virus; they are not considered eligible for vaccination. They received vaccines for the seasonal flu virus last month.

“We’ve installed a bunch of hand sanitizers in both our practice facility and here,’’ said Julien. “There are at least half a dozen or more throughout the dressing room. It’s up to us to take the precautions. If we see symptoms, it’s important to let the trainers know right away.’’

Krejci’s loss leaves the Bruins without their top two scorers from last season, and they went into last night riding back-to-back shutout losses. Marc Savard (25-63 -88) is out of the protective boot he’s worn on his broken left foot. But Savard, who is scheduled for a doctor’s visit today, has been limited to off-ice workouts and will most likely not be available until later this month. Krejci (22-51 -73) had been struggling this season, but is now out indefinitely, making Patrice Bergeron the lone up-the-middle offensive threat.

Last night, Vladimir Sobotka replaced Krejci between Wheeler and Michael Ryder. Steve Begin was promoted to the third line to center Daniel Paille and Brad Marchand. Wheeler took Krejci’s spot on the No. 1 power-play unit.

Mikko Lehtonen, brought up on emergency recall Wednesday, skated on the fourth line with Shawn Thornton and Trent Whitfield. Lehtonen started the AHL season as Whitfield’s right wing. Last night, Lehtonen landed one shot in 7:08 of ice time.

“Best player available. Let’s put it that way,’’ Julien said of bringing up Lehtonen. “We’ve called so many guys - Marchand, Sobotka, Whitfield. Now he’s the next one on the list. He has a big body, skates well, has skill. Maybe he can help us produce a little up front.’’

According to Chiarelli, discussions regarding the extension started in training camp. Rask will earn $1 million in 2010-11 and $1.5 million in 2011-12.

“We just wanted to, 1. get our goaltending situation completely cemented away for a while, and 2. give Tuukka a solid foundation so he can continue to improve,’’ said Chiarelli.

The 22-year-old Rask is 2-1-1 in his backup role to Tim Thomas. Now in his third professional season, he has played in only nine NHL games. Just last month, Chiarelli inked Milan Lucic to a three-year extension, keeping the hard-rock winger under contract through 2012-13.

“He put his time in for two years and we liked what we saw in each of the camps,’’ Chiarelli said of Rask. “We saw progression in his training camps. We saw progression in the American Hockey League. It was enough for us to come to a deal.’’

While there have been undercards - Begin (as a Canadien) breaking Savard’s back, Thornton pounding Begin the following preseason, even P.J. Axelsson dropping the gloves with perpetual irritant Maxim Lapierre - the main event has always been Lucic and Komisarek. Last year, Lucic knocked out Komisarek with a shoulder injury during a regular-season fight. In Game 4 of the playoffs, Komisarek was tossed after high-sticking Lucic in the face.

“It was pretty wild,’’ said ex-Bruin Glen Metropolit before the game. “It was pretty intense, being on both sides. Ultimately, it’s about the 2 points. It’s always fun, Bruins and Montreal. Who knows what kind of rivalry we’ll start tonight? Maybe me and [Zdeno Chara].’’

Fluto Shinzawa can be reached at fshinzawa@globe.com.