Some things are difficult to figure out. Since being traded last season from D.C. United, Union midfielder Danny Cruz had one goal in his first 19 games and none this season.

Then, in the second half of Saturday's game against Seattle, he put two in the back of the net in a one-minute span.

Cruz's heroics enabled the Union to earn a 2-2 tie with the Sounders in a feisty Major League Soccer game before 18,344 at PPL Park.

The Union (3-3-3) thought they should have received a penalty kick late in second-half stoppage time on a kick by Conor Casey, but there was no call.

"I saw a clear, blatant hand ball" by Seattle's Leonardo Gonzalez, Casey said.

The Union lost their top defender, Jeff Parke, who departed in the 44th minute with a left hamstring strain.

In the 85th minute, Union defender Sheanon Williams and Sounders midfielder Lamar Neagle got into an extended shoving match and both were shown red cards.

"The referee said we head-butted each other," Williams said, "but I never head-butted [Neagle] and he never head-butted me."

Seattle's DeAndre Yedlin was also shown a red card late in the game for a hard tackle on Michael Farfan.

Trailing 1-0 at halftime, the Union tied the score in the 50th minute when Jack McInerney crossed to Casey, whose bouncing header hit the post. Cruz then tapped in the rebound.

A minute later, a McInerney blast was saved off the crossbar by keeper Michael Gspurning. Cruz picked up an errant clear and drilled a shot from inside the box at a right angle to score.

Seattle tied the score at 2-2 when Mauro Rosales volleyed a left wing cross by Gonzalez in the 64th minute.

The Sounders took a 1-0 lead when Eddie Johnson headed in a corner kick from Rosales in the 10th minute. Shortly after, the Union failed on several scoring chances.

Right before halftime, Union keeper Zac MacMath made a point-blank save on a Johnson header.

Elsewhere: New York's Tim Cahill scored on a rebound after a penalty kick save by Luis Robles and the Red Bulls got their third straight win with a 1-0 defeat of the host Columbus Crew. . . . Former Union winger Justin Mapp scored two to give the visiting Montreal Impact the lead, but the San Jose Earthquakes fought back for a 2-2 tie.

Contact Marc Narducci at mnarducci@phillynews.com. Follow @sjnard on Twitter. This article contains information from the AP.