It was an important win, as Ottawa won earlier in the night to briefly pull even in points with the Bruins in the Northeast Division. The Bruins remain two points up with their victory, and still have four games in hand on the Senators.
The Bruins also have a huge home-and-home set coming up with the Senators, closing out their six-game road trip Saturday in Ottawa, then returning home to face the Sens at the Garden on Tuesday. Before that, the Bruins come back East but remain on the road with a stop in Buffalo on Friday.
Third Period, 19:25, Bruins 4-2: The Bruins get their first power play in the final minute as David Backes is called for goalie interference, which should end any chances for a St. Louis miracle in this one.
Third Period, 17:56, Bruins 4-2: The Blues have pulled Elliott for the extra attacker, needing two goals to tie with just over two minutes to play.
Third Period, 16:04, Bruins 4-2: The Bruins got caught back on their heels a bit for the last couple of shifts, but they've kept the Blues to the perimeter even as St. Louis has kept the play in the Boston zone. Patrice Bergeron then leads a timely breakout the other way and forces Elliott to freeze the puck for a faceoff in the Blues end.
Third Period, 13:19, Bruins 4-2: The Blues starting to press down a pair now, with David Backes firing in a shot from the right circle that Thomas smothers. Bruins with a 9-4 edge in shots this period, as they are staying aggressive and not trying to sit on lead.
Third Period, 9:14, Bruins 4-2: The Bruins get a huge insurance goal as Brad Marchand converts a breakaway chance midway through the third.
Tyler Seguin sprung him with the outlet pass and Marchand slipped the puck in 5-hole with a backhander.
Third Period, 7:04, Bruins 3-2: The Blues threaten with Chris Porter redirecting a T.J. Oshie shot in front, but Tim Thomas, who hasn't seen much action this period, makes the stop.
Boston has a 5-2 edge in shots in third, already topping the four shots the Bruins managed in second.
Third Period, 4:20, Bruins 3-2: The Bruins with some good early pressure in the third, keeping the puck in the Blues zone for long stretches here as they maintain their lead.
Third Period, 0:00, Bruins 3-2: The final frame is under way in St. Louis, where the Bruins will try to hold on to this one-goal lead and close out a win over the Blues and stay ahead of Ottawa in the Northeast Division.
The Senators have already beaten Washington to temporarily pull even in points with Boston, though the Bruins have four games in hand in addition to this one.
Second Intermission Notes: Much quieter second period, especially for the Bruins. There were no goals and no penalties in the middle frame, with the Bruins managing just four shots. St. Louis put 14 shots up and lead 24-10 overall despite Boston maintaining its 3-2 lead.
Even more telling, St. Louis has 53 shot attempts to just 23 for Boston, though the Bruins do have a 15-7 edge in blocks defensively. Dennis Seidenberg leads there with four blocked shots.
The Bruins also struggled in the faceoff circle in the second, going 8-16 after being 12-5 in the first period.
End Second Period, Bruins 3-2: There were no goals in the second after five in the first, and the Bruins maintain their 3-2 lead heading into the third period. But Tim Thomas has to make a pair of big saves on Kris Russell in the closing seconds to make sure of that.
Second Period, 19:01, Bruins 3-2: The Bruins call timeout after another icing. They have managed just four shots this period and been outshot 22-10 for the game, but still have the one-goal lead.
Second Period, 15:54, Bruins 3-2: The Bruins are struggling to get out of their own zone, getting caught out for an icing and another clear that deflected into the stands. Boston has gone 10 minutes without a shot as the offensive pace has slowed considerably in this period.
Second Period, 12:20, Bruins 3-2: Ian Walsh is back on the ice after getting repairs and we're back to a two-ref system. I prefer the old one-ref days, but injuries aren't the way to get it, so good to see Walsh back out there.
Second Period, 8:28, Bruins 3-2: The Bruins come close again as Thornton sends Daniel Paille off to the races with a high lob down the left wing. He goes behind the net and attempts a wraparound at the right post, but is denied.
Second Period, 7:31, Bruins 3-2: The Bruins come within inches of extending the lead as Johnny Boychuk blasts a shot from the right point that Patrice Bergeron tipped past Elliott. But the puck hit the crossbar and a review confirms that it never crossed the goal line.
Second Period, 6:32, Bruins 3-2: Referee Ian Walsh has gone off for repairs after taking an accidental stick to the face from David Backes. They'll play with just one ref and two linesmen for now.
Second Period, 5:35, Bruins 3-2: The Blues threaten again as Jason Arnott steals the puck from Thornton and breaks in for a bid.
Second Period, 4:12, Bruins 3-2: The scoring on the Blues' second goal has been changed. Ryan Reaves now gets credit for it, with B.J. Crombeen now getting the assist. Crombeen now needs a goal, rather than an assist, to complete the Gordie Howe hat trick after picking up a fighting major in the first against Adam McQuaid.
Second Period, 2:30, Bruins 3-2: The opening minutes of this frame have been a little calmer than the first, though Patrik Berglund did have a chance for St. Louis in the opening minute.
Second Period, 0:00, Bruins 3-2: The middle frame is under way in St. Louis, where the Bruins will look to maintain this one-goal lead after squandering a two-goal edge early in the first period.
First Intermission Notes: This one wasn't quite the defensive struggle expected, with the Bruins and Blues combining for five goals on just 16 shots. St. Louis has the 10-6 edge in shots, but the Bruins have the 3-2 advantage on the scoreboard.
David Krejci has looked solid on the wing, playing with more energy and physical presence than he's shown in weeks. He has two hits, including a huge one behind the net that helped lead to a goal, and is a plus-2 with three shots in 5:28. That line has produced two goals, with Chris Kelly and Milan Lucic each chipping in a goal and an assist.
Zdeno Chara took a hooking penalty, but after being minus-9 in his last six games, he was a plus-3 in the first period. Carter Camper played five shifts over 2:42 in his first NHL period, and was 4-0 on faceoffs centering the third line. That helped the Bruins go 12-5 (71 percent) overall on draws.
End First Period, Bruins 3-2: A wild opening frame comes to a close in St. Louis, where the Bruins will take a one-goal lead into the break after scoring in the opening and closing minutes of the period.
First Period, 19:40, Bruins 3-2: The Bruins retake the lead as Chris Kelly scores in front.
Kelly buried the chance from the top of the crease off a great feed from Milan Lucic, who passed it out from along the goal line to the right of the net.
First Period, 18:30, 2-2: The Blues continue to press the advantage, with Chris Stewart nearly scoring his second on the night as he cut in front, but clangs it off the post.
First Period, 16:00, 2-2: The Bruins kill off the penalty with big early blocks by Seidenberg and McQuaid, though Alex Pietrangelo nearly scored when he weaved through the defense for a backhand bid at the left post.
First Period, 14:00, 2-2: The Bruins will now have to kill off a key penalty as the Blues get the first power-play chance of the night with Zdeno Chara sent off for hooking.
First Period, 13:13, 2-2: The Blues threaten to take their first lead of the night as T.J. Oshie bursts down the middle, but fires wide from the slot.
First Period, 12:15, 2-2: The Blues erase the Bruins' two-goal lead as B.J. Crombeen ties it.
Crombeen scored on another turnaround shot as he pounce don the loose puck in a scramble in front, scoring this one from the right circle.
First Period, 7:17, Bruins 2-1: The Blues answer right back, getting on the board as Chris Stewart fires home a turnaround shot from the leftt circle, coming out from behind the net to pounce on the loose puck.
First Period, 6:19, Bruins 2-0: The Bruins strike again as Milan Lucic tips one in to double the lead.
after Krejci landed a huge hit behind the net, Joe Corvo launched a shot from the right point that Lucic deflected in.
First Period, 2:38, Bruins 1-0: The gloves come off right after the goal with Adam McQuaid and B.J. Crombeen squaring off for a lengthy bout.
Crombeen scored with a series of left-handed jersey jabs, while McQuaid went for power shots with his right as both men landed plenty of punches.
First Period, 2:29, Bruins 1-0: The Bruins do strike first as Brad Marchand gives Boston the early lead.
Marchand stole the puck from Kevin Shattenkirk just inside the blue line and broke in for a bid, burying it top shelf on Elliott.
First Period, 0:40, 0-0: The Bruins nearly strike in the opening minute as Lucic comes out from behind the net and sets up Kelly for a shot from the slot, but Elliott flashes out the pad to rob him.
First Period, 0:00, 0-0: After a pre-game ceremony honoring Bay State native and U.S. Hockey Hall of Famer Keith Tkachuk, this one is under way in St. Louis.
8 p.m.: The Bruins won't have to wait to see how David Krejci looks on the wing, as he'll start this one on the right side of a line with Milan Lucic and Chris Kelly. Dennis Seidenberg and Joe Corvo open on defense, with Tim Thomas in goal.
The Blues counter with David Perron, Andy McDonald and Patrik Berglund up front, Roman Polak and Kris Russell on the blue line and Brian Elliott in net.
7:55 p.m.: Josh Hennessy and Andrew Bodnarchuk are the healthy scratches for the Bruins. Shawn Thornton will play and Carter Camper will make his NHL debut for Boston.
Kent Huskins and T.J. Hensick are out for St. Louis.
7:30 p.m.: Tim Thomas and Brian Elliott led the teams out for warm-ups and will be the starters in goal for this one as expected.
Shawn Thornton is on the ice for warm-ups, but a final decision on his status for this one won't be made until the Bruins see how he fares in the pre-game skate.
7 p.m.: The Bruins will look to snap a two-game losing streak against one of the top home teams in the league as they continue their road trip in St. Louis.
They may have to do it without Shawn Thornton, who missed the morning skate with an illness and will be a game-time decision.
With or without Thornton, the Bruins' forward lines will look a little different with David Krejci moving to wing and Carter Camper potentially making his NHL debut.
8 a.m. ET: The Bruins will look to awake their slumbering offense as they continue their season-high six-game road trip in St. Louis, but that is not the easiest place to score goals these days.
The Blues are 26-3-4 at home this season, second only to Detroit's 26-2-1 mark thanks to the Red Wings' current NHL-record 23-game home winning streak. The Blues are 36-16-17 overall, good for 79 points and fourth place in the West, five behind Central Division and conference-leading Detroit.
The Blues have a streak almost as impressive, having not lost in regulation at home since a 5-2 setback to the Blackhawks on Dec. 3. They're 18-0-3 at home since, including 5-0-0 with three shutouts on home ice since the All-Star break, though they are coming off a 3-1 loss in Chicago on Sunday.
St. Louis has allowed an NHL-low 117 goals, just 1.88 a game, and is the first team in NHL history with two goalies with six or more shutouts in the same season, with Brian Elliott (20-6-2, 1.56 GAA, .940 save percentage) and Jaroslav Halak (16-10-5, 1.97 GAA, .923 save percentage) each having a half dozen already.
That's not good news for a Bruins team that's been shut out four times in its last nine games. Boston has just 15 goals overall in its last 11, going 4-7-0 in that stretch, which coincides with the absence of forward Nathan Horton (concussion). Rich Peverley (knee) has also missed the last two games, with the Bruins falling 4-2 in Winnipeg and 2-0 in Minnesota.
Boston now stands at 35-20-2. The Bruins remain in second in the East thanks to leading the Northeast Division, but they actually have just the fifth-most points in the conference behind Atlantic Division powers the New York Rangers (81 points), New Jersey (74), Philadelphia (73) and Pittsburgh (73).
Boston's lead in the Northeast is down to two points on Ottawa, though the Bruins do still have four games in hand on the Senators, who host Washington on Wednesday.
The puck drops at 8 p.m., so check back here for updates on all the action.