The Fire lost its most dangerous player, midfielder Peter Nowak, to a knee injury halfway through the game and then had to play a man short for 40 minutes after defender Evan Whitfield was red-carded.
Even with those two advantages, Los Angeles just couldn't quite manage a victory, and instead grudgingly settled for a 1-1 tie in front of a rain-soaked crowd of 10,388 at Soldier Field.
The Galaxy might have won Game 1 in the best-of-three semifinal series had Cobi Jones' goal three minutes into sudden-death overtime not been disallowed by referee Kevin Stott, who ruled that Brian Mullan had fouled DaMarcus Beasley seconds earlier.
Mullan, playing his first game in four months after ankle surgery, denied making any contact with Beasley.
"I didn't touch him at all," he said. "I slid, played the ball to Cobi and he [Beasley] jumped up in the air and fell down."
The Galaxy might also have won had Mauricio Cienfuegos found a way to beat Chicago goalkeeper Zach Thornton one minute later after Jones had gotten in behind the Fire defense and set Cienfuegos up for a close-range shot.
Instead, Thornton appeared from nowhere to block the effort. Afterward, the Galaxy locker room was a scene of ice packs and long faces.
"We were under pressure in the first half and then we slowly got back into the game, but playing against a team that's a man down we should have done a lot better than we did," said midfielder Simon Elliott.
Galaxy defender Ezra Hendrickson lasted only 34 minutes after suffering a hip injury that makes his status questionable for Saturday's Game 2 at Cal State Fullerton's Titan Stadium.
"Hopefully I can be back; I've got two days to deal with it," said Hendrickson, who has been the Galaxy's most valuable player this season.
Like most Los Angeles players, Hendrickson thought Jones was robbed of a legitimate goal.
"We went a man up and had our chances," he said. "We actually put one away but it got called back on a questionable foul. Now we know we have to play three games. First we've got to go home, get three points there, and then come back here and do what it takes." The Fire dominated the first half, with Dema Kovalenko hitting the post in the opening minute before Eric Wynalda finally put Chicago ahead in the 32nd minute.
A Nowak run up the middle set up the goal, the Polish playmaker feeding Beasley on his left, a move that caused Galaxy goalkeeper Kevin Hartman to race out of his net to deal with the threat. Beasley responded by sliding the ball across for Wynalda to steer it into an empty net.
One minute before halftime, Los Angeles tied it. Adam Frye, who had come on in place of Hendrickson, floated a cross from the right wing, Sasha Victorine threw himself forward in an effort to reach the ball but was tangled up by defensive midfielder Chris Armas.
Stott, who might have considered it incidental contact, awarded the Galaxy a penalty kick.
Luis Hernandez took it and his poorly struck shot was blocked by Thornton, diving left, but the ball rolled free and Hernandez tucked in the rebound to tie the score.
Hristo Stoitchkov came on in place of the injured Nowak for the second half, but the Fire lacked the cohesion it had exhibited earlier. The Galaxy took advantage, lifting its game in an effort to break Chicago's nine-game unbeaten streak at home in MLS playoff competition.
It was a compelling game, filled with moments of high drama, but it left both coaches angry at the outcome.
"I have a little bit of mixed emotions," said the Galaxy's Sigi Schmid. "When they got the red card [in the 60th minute when Whitfield threw a body block at Jones that left him groggy] we obviously had an opportunity, playing 11 against 10. I'm disappointed we didn't take advantage, but on the other hand, I don't think tonight was our best game.
"We didn't keep possession of the ball real well and Chicago took it to us. So not playing well and still coming out with a point is a plus." Bob Bradley, Chicago's coach, didn't think a tie was a fair result.
"We don't think so," he said, pointing out that the two biggest calls of the game--the penalty kick and expulsion--had gone against the Fire. "It [the tie] doesn't seem fair."