PHILADELPHIA, May 15 (UPI) -- Jeoffrey Lupul scored the first of Philadelphia's three opening-period goals Thursday and the Flyers kept their season alive with a 4-2 victory over Pittsburgh.

The Penguins lead the Eastern Conference Finals 3-1 and will try to earn a spot in the Stanley Cup Finals at home Saturday in Game 5.

Philadelphia scored more goals in the first period Thursday than it had in any of the first three games of the series.

Lupul scored on a slapshot 8:27 into the game and the Flyers then got power-play goals from Daniel Briere and Jeff Carter to take a 3-0 lead after one.

Pittsburgh got two goals from Jordan Staal in the third period, the second coming with 5:49 remaining in regulation, but Martin Biron was perfect the rest of the way and Lupul clinched it by scoring into an empty net with 32 seconds to play.

Biron made 36 saves and Pittsburgh's Marc-Andre Fleury had 30.

The loss was only the second for the Penguins in this year's playoffs. The Penguins swept the Ottawa Senators in the opening round and defeated the New York Rangers in five games in the conference semifinals.

MLB inter-league play set to begin

NEW YORK, May 15 (UPI) -- The first of two yearly Major League Baseball inter-league periods is set to begin, with the American League riding a four-year winning streak.

A total of 252 games will be contested in the two periods, with the first getting under way Friday and the second running from June 13-29.

The AL recorded a 137-115 record against its National League foes last season, with a .281 batting average and 1,352 runs.

The American League's record in the past four seasons is 554-454, a .550 percentage.

At 14-4, Detroit and the LA Angels of Anaheim shared best record honors.

The overall attendance was about 7.3 percent higher than season's average intra-league attendance of 32,529.

The first match-ups in this season's inter-league schedule include Washington at Baltimore; Milwaukee at Boston; the New York Mets at the New York Yankees; the LA Dodgers at the LA Angels; and Houston at Texas.

In Friday's lone intra-league battle, Pittsburgh plays the Cubs in Chicago in a National League series.

Yankees fall into last place

ST. PETERSBURG, Fla., May 15 (UPI) -- Shawn Riggans' fourth-inning two-run homer Thursday helped the Tampa Bay Rays top New York 5-2 and send the Yankees into the Eastern Division cellar.

Tampa Bay's other runs came on Akinori Iwamura's solo homer in the first and sacrifice files by Carl Crawford in the third and B.J. Upton in the fifth.

Riggans and Iwamura combined for four of the Rays' five hits. Tampa Bay defeated the Yankees three times in the four-game series.

Winner Scott Kazmir (2-1) gave up three hits in six scoreless innings. After Gary Glover was touched for two runs in the eighth, closer Troy Percival earned his 10th save.

New York's Melky Cabrera and Derek Jeter both had two hits and one RBI.

Ian Kennedy (0-3) surrendered five earned runs and five hits in five innings to take the loss.

At two games below .500, the Yankees slid a half game behind Toronto into the American League East basement. Tampa Bay leads the division by a game over Boston.

Sorenstam shares lead at Sybase Open

CLIFTON, N.J., May 15 (UPI) -- Annika Sorenstam, two days after announcing her upcoming retirement from competitive golf, shared the lead Thursday after one round of the Sybase Classic.

After her announcement Tuesday that she would step down at the end of this season, she threw out the first pitch at a New York Mets game and appeared on a late-night, network television show.

She then went out Thursday and shot a 5-under 67 at the Upper Montclair Country Club and was tied for the lead with Song-Hee Kim and Rachel Hetherington.

Two-time defending champion Lorena Ochoa, who has supplanted Sorenstam as the No. 1 player in women's golf, was one shot back.

"It's been a busy week, so it was kind of nice this morning to tee off and then walk inside the ropes," Sorenstam said.

Several members of the gallery called out pleas to Sorenstam not to retire.

Ochoa has failed to challenge in either of her last two starts after winning four straight tournaments. Sorenstam won last week's Michelob Ultra Open.