DALLAS – Maybe Dallas thought it was going to be that easy. A decided favorite going into their first-round series against Colorado, the Stars already had a two-goal lead.

Except there were more than two periods left in what turned into a 5-2 victory by the seventh-seeded Avalanche.

Colorado cut the deficit in half before the end of the first period, then scored three times in the second period. Rookie winger Wojtek Wolski tied the game at 2 before Rob Blake and John-Michael Liles scored on power-play goals only 2:04 apart.

Joe Sakic, the Avs captain and leading scorer, had two assists to start his 12th playoff appearance. Goalie Jose Theodore stopped 16 shots in only his sixth game for Colorado.

Game 2 is Monday night in Dallas.

The Avalanche certainly looked like a playoff-seasoned team, one starting its 25th playoff series since moving to Denver in 1995 – more than any other team. Not the squad that lost 10 of its last 16 regular season games for its lowest playoff seeding since 1987 while still in Quebec.

For the Stars, it was eerily similar to their last playoff series two years ago. Colorado won that first-round series in five games and twice scored five times against Dallas goalie Marty Turco.

This is the fourth time in seven years the two teams have meet in the playoffs. Dallas won a pair of incredible seven-game Western Conference finals in 1999 and 2000 to get to the Stanley Cup finals.

Dallas went up 2-0 when Jason Arnott slid by the net and made a backhand pass to Bill Guerin, who slammed the puck behind Theodore with 4:58 left in the first period.

That came only two minutes after a one-timer by Brenden Morrow on Dallas’ third shot of the game. Stu Barnes made a pass from behind the net to Morrow at the edge of the right circle.

But the Stars didn’t hold on to that momentum very long.

With Turco sliding to his right, Sakic pushed the puck back toward the middle and Milan Hejduk knocked it into the open net with 3:18 left in the opening period.

Another defensive mistake led to Colorado’s tying goal 51/2 minutes into the second period. Turco was still on the side of the net after playing the puck when defenseman Jon Klemm gave it away. Jim Dowd passed the puck to Wolski and Turco couldn’t get back in time to prevent the goal.

After Blake’s power-play goal, a puck through traffic that Turco didn’t see until it was too late, there was only 15 more seconds of play before Colorado was on the power play again. Liles scored past a sprawling Turco for a goal assisted by Sakic and Andrew Brunette.

Turco stopped 26 shots, but has allowed 23 goals in six playoff games against the Avalanche.

Theodore was 1-3-1 down the stretch for Colorado. The former league MVP didn’t make his debut for the Avalanche until a month after coming from Montreal at the NHL trade deadline March 8 for David Aebischer, the goalie who beat Dallas in the series two years ago.

The Stars didn’t make Theodore work too hard after their first two goals. Dallas only had four shots in the second period, and their nine in the third period matched their total before that.

Notes: Wolski is a rookie who had 128 points in 56 games in the Ontario Hockey League before being added to Colorado’s playoff roster. … Dallas had a 3-1 advantage in the season series, two of the wins coming in shootouts.

AP-ES-04-22-06 1758EDT