Landon Donovan's fourth career MLS hat trick was not enough to give the Los Angeles Galaxy a victory.
Blas Perez scored his second goal in the 86th minute to lift FC Dallas into a 3-3 tie with the Galaxy on Sunday night.
Donovan scored twice within nine minutes to give Los Angeles a 3-2 lead in the 82nd minute, but Perez notched his team-leading eighth goal of the season four minutes later.
Dallas nearly won it in stoppage time when Jackson launched a 40-yard shot that went off the right post.
"I really feel like the ball was going in," said Jackson through a translator. "I was really confident I took a really good shot that I thought was going in."
The draw lifted the Galaxy (10-9-4) into a fifth-place tie with Seattle in the Western Conference.
Dallas (8-6-9), which had its winless streak extended to 10 matches (0-4-6), remains one point behind.
"We felt good about ourselves but we got lazy, gave up a real easy, careless free kick and then they score a goal," said Donovan whose hat trick was his first in an MLS game since 2008.
"At the end of the day, it's good we fought back, but when you have the lead with five minutes to go, you should win the game."
All three Dallas goals originated off set pieces (one from a corner kick and two via free kicks), marking a league-leading 10 such goals the Galaxy have allowed this season.
"It's been the story of the whole year with our set pieces, where we fall asleep and they end up getting a goal," Galaxy defender Omar Gonzalez said.
"It's just a matter of putting everything you have into that 15-30 second play. It just has to be better. Our fight has to be better, more than the guy we're going up against and tonight it just wasn't there.
The Galaxy also felt that Perez's tying goal, and perhaps his first one, should have been called offside.
"Terrible officiating, no question about it," LA coach Bruce Arena said.
"However, we were still in position to win the game. What more can you say? It's a shame that we can't get better officiating in these games. We're the team that should have won this game. It's a shame, it really is."
Matt Hedges scored Dallas' other goal in the 15th minute, snapping a club-record goalless streak at 464 minutes, the seventh-longest drought in MLS history.
"It's important that the goals were scored and that bad run is finished," Dallas midfielder David Ferreira said through an interpreter.
"But at the same time, there is sadness and the feeling in the locker room is that this was a game that the team could have taken the three points. That didn't happen, so the feeling is kind of mixed."
Chris Seitz made five saves for FC Dallas in just his third appearance this season. He filled in for starter Raul Fernandez, who is with the Peru national team.
"It was an exciting game with two teams that played really hard," Dallas coach Schellas Hyndman said.
"I thought it was a good performance on our part in regards to team energy, hard work, we battled for balls. When we were down, we continued to fight, showed a lot of character playing against a very good team. I just wish the wind would have blown that ball in when it hit the post. That was a great shot by Jackson."
With Dallas ahead 2-1, Donovan received a short pass from Marcelo Sarvas and stepped into a right-footed shot from 18 yards that beat the diving Seitz just inside the right goal post in the 73rd minute.
Nine minutes later, a throw-in by Robbie Keane bounced to Donovan about 8 yards out and the U.S. national team star spun and drilled a right-footed shot past Dallas defender George John. The ball initially appeared to be going wide, but it curled just inside the far post and in.
Perez tied the score off a free kick by Michel from 25 yards. The ball sailed into the middle of the penalty area, where Gonzalez headed it out, but it went right to Perez, who fired a 15-yard shot that beat Galaxy goalkeeper Carlo Cudicini just inside the left post.
Perez snapped a 1-1 tie in the 48th minute on another play that was set up by a free kick from Michel, who had entered the match to start the second half. His looping free kick from 30 yards curled toward the left post, where Perez lunged with his left foot to re-direct it home.
Hedges scored his second goal of the season, and FC Dallas' first in six games, to give his side a 1-0 lead just 15 minutes in. Ferreira delivered a corner kick into the middle, where George John headed it down. The ball bounced past several players to Hedges, who headed it just inside the left post.
Donovan's first of the game tied it during first-half stoppage time, when he got past Hedges to chase down a nice lead ball from Keane and head it over the charging Seitz.
Keane, L.A.'s leading scorer and captain, was back in the lineup after missing three league games with a hip flexor injury.