Jon Busch made a number of quality saves, and Chris Wondolowski netted the lone goal to propel the Earthquakes up the MLS table.
In a free-flowing half, neither team was able to get an edge on the scoreboard. And, despite the up-and-down play, the number of chances were limited.
Philadelphia had the better of the quality chances with Stefani Miglioranzi leading the efforts. In the 22nd minute, Miglioranzi received a drop pass from Alejandro Moreno and hammered a shot from long distance. Quakes keeper Jon Busch laid out and stopped it.
In the 37th minute, Miglioranzi again ran onto a ball rolling away from goal. This time, from about 35 yards out, he drilled a shot that handcuffed Busch, but he was able to pounce on the rebound before any Union player could.
And in the 41st minute, the Union again had a solid chance go awry when Sebastian Le Toux found Moreno at the top of the box with an open lane to shoot. Moreno's strike wasn't as solidly hit as he would have liked, but it still was heading for the far post. Busch again made a diving effort to stop it from hitting the side netting.
San Jose had fewer chances, and they were far less threatening. In the eighth minute, Bobby Convey whipped a cross into the box that found Chris Wondolowski, but his shot was blocked and the rebound try by Geovanni was also blocked.
Wondolowski tried again in the 27th minute with a long range strike that trickled on goal, but Brad Knighton stopped it with relative ease.
And to conclude their chances, Khari Stephenson took a shot from near 40 yards in the 42nd minute that Knighton mishandled, leaving the ball for the taking. Wondolowski ran onto it, but as he met the ball, he was whistled for being offside.
Little happened in the opening stages of the second half. It wasn't until the 56th and 57th minutes when the Earthquakes had three consecutive corners and put pressure on the Union defensive unit. But their third attempt didn't prove to be a charm, instead it was simply a dud that went out for a goal kick, keeping it scoreless.
In the 62nd minute, Knighton finally showed some confidence in his play, racing off his line to punch away an Earthquakes cross that was heading right for Geovanni's head.
Then in the ensuing rush up the field, Shea Salinas, a former Earthquake, sent a ball to Fred at the top of the box, but his shot was off target.
Finally in the 69th minute, there was some action in a second half that was approaching new levels of boredom.
San Jose maintained control of the ball on the left flank. A cross sent into the box went all the way to the other side for Arturo Alvarez who sent it back into the box. Wondolowski was perfectly positioned and headed it with precision into the corner, just out of the reach of Knighton.
Philadelphia gave a little scare to the Quakes, but it was nothing they couldn't handle. Le Toux appeared to be through in the 83rd minute, but Busch came out to dive and knock the ball out of harm's way.
The Union had a number of corners over the next three minutes, but the Quakes defense toughened up and prevented any Union player to win a 50-50 ball, keeping them off the board.
With the Union pressing forward, the Quakes made a quick counter and almost capitalized. Convey got free up the left flank and sent a hard-hit, low cross that was just out of the reach of Eduardo and over the end line for a goal kick.
And in the 89th minute, Geovanni took a free kick from 30 yards out trying to extend the Earthquakes lead. His shot was heading for the upper 90, but Knighton laid out and pushed it over the bar.
In stoppage time, the Union had the final chance of the game, but Busch came up with a solid stop to save the Quakes win. Philadelphia had a free kick on the end line outside of the box to Busch's right. In a scramble, the Union managed to put a shot on target, but Busch was in the right spot, grabbing the ball, preserving the clean sheet.
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