DETROIT – The Dallas Stars haven't made life easy for themselves in the playoffs.

They have fallen behind in seven of their 13 postseason games. Poor first-period play continues to haunt them.

The Stars haven't scored a first-period goal in almost two weeks, a span of five games. Dallas has gone a full month since its last first-period power-play goal.

"We've been a great third-period team throughout the spring, and it's won us some games," Mike Modano said, "but it would be nice not to make it so difficult on us at the end."

The Detroit Red Wings took a 2-0 lead against the Stars in the first period of Game 1 of the Western Conference finals Thursday, and coasted to a 4-1 victory.

The Stars found out it is one thing to fall behind against Anaheim and San Jose – a pair of low-scoring, defensive-minded teams – but quite another to have to rally against the up-tempo Red Wings. Detroit was an NHL-best 43-5-2 when scoring first in the regular season and is 7-1 in the playoffs.

Captain Brenden Morrow said he can't explain the Stars' first-period woes.

"We focus. We prepare. We do all the right things to get ready for games," Morrow said, "and it's anyone's guess why the first is our worst."

But centers Brad Richards and Mike Ribeiro and winger Steve Ott say they have the problem figured out.

They point to too many penalties in the first period, forcing the Stars to spend much of their time on the penalty kill.

The Stars are averaging 1.5 penalties per period in the playoffs, but almost twice that many – 2.8 – in the first period. All told, 51.4 percent of the Stars' playoff penalties have come in the opening period. They've committed at least two first-period penalties in 12 of their 13 playoff games, including four games with four first-period penalties.

The Stars' four first-period penalties in Game 1 against the Red Wings led to two power-play goals.

Ott called penalties "your worst fear," noting that killing penalties takes skill players such as Ribeiro out of the game. "You need guys like that getting on the ice and getting into a routine and a rhythm," Ott said.

The Stars have one first-period goal in their last eight playoff games – it came in Game 2 against San Jose – and that's a two-part problem: too many early penalties and an ineffective power play.

The Stars have two first-period power-play goals in the playoffs, and both came in Game 1 of their first-round series against the Anaheim Ducks. Since then, the Stars are 0-for-18 on first-period power play chances.

First is worst

More than half of the Stars' postseason penalties – 36 of 70 – have been committed in the first period. Here's the breakdown for the 13 games with penalties in the first period and total penalties for the game.