As Ryan Raybould ’05 and his teammates celebrated his second-half goal that put the men’s soccer team up 1-0 against the University of Pennsylvania, it seemed Yale was minutes away from victory in a huge Ivy League contest between the two teams.

But within seconds, all bets were off as the Quakers (9-2, 4-0 Ivy) erased Yale’s lead, then took one of their own to beat the Bulldogs (8-3-1, 1-2-1) 2-1 before a crowd of 1,004 at the Soccer-Lacrosse Stadium Saturday night.

“They’re having that kind of season where things break in their favor,” Yale head coach Brian Tompkins said of the Quakers, who remain undefeated in the Ivy League. “You can dominate the game, but it’s a matter of who scores more.”

The loss was heartbreaking for the Elis, who played a crisp and precise first half but were unable to find the back of the net when they had the chance. Furthermore, it all but guaranteed that Yale will not win the Ivy League this season.

With Princeton’s defeat of Harvard this weekend, Penn now is the only Ivy team without a loss, and the Quakers would have to lose two of their remaining three games in order to open the door for another team.

For the first half of the game, the Elis controlled the ball for the majority of time and recorded seven shots on goal. But Quaker goalie Matthew Haefner showed why he is among the best goalies in the nation in goals against average, stopping all of Yale’s first-half opportunities except one.

Just 20 minutes into the game, forward Justin Burton ’04 fed Lindsey Williams ’05 with a pass, which Williams drilled past Haefner to the delight of teammates and fans. But an offsides call nullified Williams’ effort.

Strong defensive play by Steve Gibbons ’03 and Ryan Morrissey ’06 stopped several Penn chances, and captain Stu Yingst ’03 was dominant until he had to leave the game early in the second half with an injury.

The two teams went into halftime in a scoreless tie, which was an accomplishment for Penn. Their ability to keep Yale off the scoreboard prevented the Elis from taking advantage of their first-half dominance and establishing an early lead.

“In the first half we were far more dominant in our play and we created a lot of danger,” Tompkins said.

In the second half, Yale continued to be in control and notched their first legitimate score when Williams got the ball to Raybould on the right side. Raybould put the ball just inside the right goalpost to give the Elis the lead.

At that point, Yale seemed to be in complete control, having both the momentum and the lead.

But Penn kicked off at midfield and took the ball straight to the goal. While the Quakers’ first shot hit the crossbar, Quaker forward John Rhodes collected the rebound and blasted a shot to the lower right corner to tie the game at one.

“That goal was huge,” Penn head coach Rudy Fuller said. “If we’d not answered right away I’m not sure we would have pulled it out.”

As it was, Penn was able to pull it out. With 17 minutes remaining in the game, Stephen Kroculick took off on a breakaway toward the goal and shot a slow-rolling ball that broke the tie — and the Bulldogs’ hearts — as Penn jumped ahead to a 2-1 lead.

The remainder of the game was frustrating for Yale as Penn retreated into a defensive shell for the rest of the night.

An offensive flurry with five minutes to go followed by a near goal by forward Andrew Dealy ’05 nearly tied the game, but ultimately Penn pulled out the victory.

Both teams’ coaches complained of poor officiating and questionable calls throughout the game.

“I just think that the speed of the game required that it be managed a lot better than it was,” Tompkins said. “I wasn’t happy with the way it was managed.”

The Quakers have yet to face Harvard, Princeton and Brown in their quest for the Ivy title.

“We were joking before the game that we felt that Yale and Harvard are the best two teams in the league, and Brown and Princeton are the two defending champions,” Fuller said. “We still have our work cut out for us in a big way.”

If the Elis are to be one of the 48 teams that qualifies for the NCAA tournament, they have even more work ahead of them to make up for the ground they lost this weekend.