DALLAS - The Flyers did not practice Thursday or Friday, and they didn't show up for Saturday afternoon's second period, either.

Dallas scored four unanswered, second-period goals - including a natural hat trick by center Tyler Seguin - as it defeated the Flyers, 5-1, at the American Airlines Center.

The Flyers (13-14-2), now 2-2 on the six-game road trip, missed a chance to go over the .500 mark for the first time this season.

The line of Seguin (four points), Valeri Nichushkin (four), and Jamie Benn (one) combined for nine points and a plus-11 rating - and had too much speed for the Flyers.

"We made a couple mistakes with those guys on the ice in the second period, and it was in our net," coach Craig Berube said.

After an impressive first period in which they overcame a seven-minute Dallas power play that resulted from a Zac Rinaldo fight - the winger got a game misconduct - and took a 1-0 lead on Andrej Meszaros' late goal, the Flyers were thoroughly outplayed in the second.

They had just six shots, had no cycle, and allowed numerous odd-man rushes - and the four goals.

Thirty-nine seconds into the second period, Seguin tied it while on a two-on-one with Benn. The Stars then scored three goals in a 1:02 span late in the period to take a 4-1 lead.

Goalie Steve Mason had little support in front of him, and it marked the first time in 28 games with the Flyers (21 this season) that he had allowed more than three goals in a game.

"Without Mason making six or seven unbelievable saves, it could have been 9-1 after the second," said winger Scott Hartnell, who played in his 900th career game.

Mason was replaced by Ray Emery to start the final 20 minutes.

Dallas, which got a late shorthanded goal from Cody Eakin, had lost its last six against the Flyers since 2008.

Rinaldo went after Antoine Roussel 1:15 into the game and launched a flurry of punches to the head, sending the Dallas forward to the ice.

Rinaldo was given two minutes for instigating, five minutes for fighting, a 10-minute misconduct, and a game misconduct. He played four seconds and totaled 27 minutes in penalties.

"Stupid," Berube said of Rinaldo's actions.

In an oddity, Rinaldo was the only one penalized for the "fight."

Should the league suspend Rinaldo, the Flyers may recall a forward (Tye McGinn?) if center Vinny Lecavalier cannot play Monday in Ottawa.

Lecavalier, who has been bothered by back spasms, skated Saturday morning and did "so-so," said assistant general manager Ron Hextall, adding the center was "possible but not probable" for Monday.

Breakaways. Defenseman Kimmo Timonen left the game late in the second period with an unspecified upper-body injury and was limping around after the game. He is day to day, and Hextall said he didn't believe it was serious. . . . Dallas was missing two of its key defensemen, Stephane Robidas and Trevor Daley, who were sidelined with injuries. . . . Backup Stars goalie Dan Ellis notched the win. . . . The crowd was announced at 8,567 in the 19,099-seat arena as fans stayed away because of icy road conditions.