The Boston Bruins can't afford to take a period off, regardless of how well goaltender Tim Thomas is playing.
Boston looks to rebound from its first loss in four games when it hosts the Dallas Stars on Saturday night.
In Thursday night's 3-2 loss at Calgary, the Bruins (5-3-3) had their three-game win streak snapped as they allowed two second-period power-play goals. Boston hadn't allowed a power-play goal in its three previous games.
"In the second period we got into penalty trouble," Bruins captain Zdeno Chara told the team's official Web Site. "I think that cost us a lot of energy and (lost us) the momentum of the game and they scored two goals. That was a really disappointing period for us."
Dion Phaneuf scored 2:29 into the second to end Thomas' shutout streak at 152 minutes and 14 seconds. Thomas was coming off back-to-back 1-0 shutouts against Edmonton and Vancouver on Monday and Tuesday, respectively.
The Bruins were outshot 20-9 in the second period when the Flames converted two of their four power-play opportunities.
"We're really trying to take pride in our penalty killing and we've done a really good job lately but when you take that many penalties that close together, eventually Calgary broke us down," said Thomas, who stopped 37 of 38 shots in his only career appearance against Dallas - a 2-1 shootout loss in Boston on Jan. 14, 2006.
Dallas (4-5-2) is hoping for a similar result in its return to Boston after opening a five-game road trip with a 5-2 loss to Chicago on Friday.
The Stars had nearly an identical record (5-4-2) through 11 games last season as they would advance to the Western Conference finals, but that similarity doesn't help alleviate this season's struggles.
"It's frustrating after 11 games to be where we are," captain Brenden Morrow told the team's official Web site.
Morrow had an assist as Loui Eriksson gave Dallas a 1-0 first-period lead, but the Stars were outshot 32-23 and went 0-for-5 on the power play, including a 5-on-3 in the second period where they didn't get a shot.
"Our play with the puck wasn't very good," center Mike Modano said. "We are not coming up ice in-sync and making good passes. We are chasing from behind. We are having lots of breakdowns and it's been a long time since I've seen that many odd-man rushes against. We are over-pursuing and trying to do too much."
Dallas, which has the NHL's worst goals-against average at 4.09, started backup goalie Tobias Stephan for the second straight game, but likely will switch to Marty Turco on Saturday. Turco, who has a league-high 4.26 GAA in nine starts, is 4-1-0 with a 0.79 GAA and one shutout in five career starts against the Bruins.
The Stars were without three key players Friday, as center Brad Richards (lower body), right wing Jere Lehtinen (groin) and defenseman Sergei Zubov (hip) all sat out. The team did not disclose how long Richards would be sidelined, but Lehtinen is day-to-day and could return within a week while Zubov is expected to make his season debut Friday at Anaheim.
Dallas is 4-1-0 with a tie in its last six games in Boston.
By the Associated Press with edits by BostonBruins.com