SAN JOSE, Calif. - An aging soccer shark put the bite on the Earthquakes Saturday night. 

Second-half substitute Conor Casey, in his first action in more than a month, nodded in two goals in an 11-minute span as the Philadelphia Union rallied for a 2-1 win at Avaya Stadium.  

Now the Quakes, who saw their four-game winning streak come to an abrupt halt, will look to rebound in a huge game against the Seattle Sounders on Saturday night at Avaya Stadium, when a victory might push them above the red line in the Western Conference.  

"We've beaten (Seattle) twice already this year. It's not going to be easy, but we do like our chances with some guys returning to the lineup and us playing at home," Clarence Goodson said. "We've beaten some very quality opponents, so we know we can get it done."  

On Saturday, the Quakes took a huge hit when Victor Bernardez, Goodson's center-back sidekick, suffered a hamstring injury in the 39th minute and was replaced by midfielder JJ Koval. The team was already playing without midfielder/international call-ups: Anibal Godoy (Panama), Marc Pelosi (U.S. U-23 national team) and Sanna Nyassi (Gambia). Designated player Innocent has been out since May.

But the Quakes had enough to get the job done. Mental lapses and marking mishaps factored into the unlikely result.
Coach Dominic Kinnear said the team gave the ball away on both Philly goals -- an MLS no-no. 

"So that's the mistake," Kinnear said. "And then the second one we didn't need to foul when we did. It was a continuance of turnovers that kind of came back to bite us, and we didn't mark well on the set piece. That was pretty evident." 

The Quakes were off form in the first half against a sagging defense. It took them too long to get rolling on counters, which seemed to play right into the Union's strategy.  

Designated player Matias Perez Garcia looked dangerous at times in his return from an injury, but his explosive forays didn't produce the desired result. The Quakes started sharply in the second half, and the surge nearly produced the game's first goal in the 47th minute, when Quincy Amarikwa hit a curling shot off the post off a flicked pass from Wondolowski.  

The Quakes appeared on their way to No. 5 in a row when Wondolowski broke the tie in the 63rd minute with a penalty kick after a handball by Fabinho.

Rewind: Quakes to learn from mistakes against Union in preparation for Seattle -

But things fell apart after Casey entered and delivered a performance reminiscent of the 2012 version of the "Bash Brothers" Steven Lenhart and Alan Gordon, who had a knack for breaking opponents' hearts in the final minutes. 

Casey broke the Quakes' 447-minute shutout streak in the 74th minute with his second goal of the season. After a cross from Raymon Gaddis went just over Goodson's head, Casey's redirected header found the net. In the 85th minute, Casey lost his marker and scored the winner on a set piece after an ill-advised foul by the Quakes. 

"He has been a thorn to many clubs' side," Wondolowski said Casey. "He's been doing this for years. He's a great player, a great force in the box and a great finisher. He displays good movement and creates that little bit of space he needs." 

The Quakes have been able to get away with their mistakes at times, such as committing sloppy fouls just outside the box. Not this time.

"We have to learn from our mistakes," Wondolowski said. "It's too late in the season to be making those errors. We mentally turned off for two plays and we paid for that dearly; it lost us the game. We had turnovers that led to those chances. Lastly, you have to do a better job marking someone like Conor Casey. When he is open in the box like that, it is never good." 

At halftime, Kinnear simply told his players simply to play a little better and try not to force things. 

"We just needed to move the ball quicker," Kinnear said. "They were sitting in pretty tight, and there wasn't a whole lot of space, so to move the ball faster and get it wider quicker and maybe move them around a little bit better. So that was one of the thoughts. Another thought was try and spin them around a little bit, but they were sitting deep, so there wasn't a ton of space in behind. So to have some patience, but to play with urgency. Let's not force anything. Play with simple passes, but move it around a little bit quicker."