The Sounders led 2-0 and 3-1, but both times their lead grew to two goals, Chicago rookie-of-the-year candidate Harrison Shipp was there to halve the lead.
Along the way, Martins matched Clint Dempsey for the club lead with his seventh and eighth goals of the season, but he also picked up a red card just before halftime for "striking the head of an opponent."
Both teams played the second half with 10 men, as Chicago defender Jhon Kennedy Hurtado, who played the previous five seasons with Seattle, was sent off in the 37th minute with his second yellow card.
The win sends Seattle into Major League Soccer’s World Cup break with the best record in the league: 10-3-2. With 32 points through 15 games, they are on pace for 72 points over the 34-game season, which would be an MLS record.
Chicago fell to 2-4-8 and remains the only MLS team never to have beaten the Sounders.
As wild as the game eventually became, its first 30 minutes played out scorelessly. The best chance had come early as Chicago goalkeeper Sean Johnson raced to the top of the penalty box, but missed his try for the ball. It rolled deep into the area, where Martins caught up to it, but shot wide across the open goalmouth.
However, he connected in the 31st minute when he took a deflected Brad Evans pass with his back to the goal, turned and fired from about 8 yards.
Martins next goal came on the penalty kick that followed the foul that sent Hurtado from the match.
However, Shipp answered about three minutes later, working his way between defenders Chad Marshall and Evans.
Lamar Neagle seemed to give the Sounders breathing room again in the 78th minute, when he patiently waited for a high-bouncing ball, then touched it into position and fired past Johnson.
Shipp answered again four minutes later. However, the Fire couldn’t get an equalizer past Sounders goalkeeper Stefan Frei, who recorded three saves.
The Sounders will be given most of this week off. They will return to training on Saturday (June 14) in advance of their June 18 entry into U.S. Open Cup.
Their next MLS match will come June 28 at D.C. United. Martins will miss that game unless his card is rescinded.
I'll be back with some quotes as they arrive from Illinois.82' GOAL Chicago. Harrison Shipp gets his second of the game as Fire returns within striking distance. Seattle, 3-2.
78' GOAL Sounders. Patience, patience, patience pays off for Neagle, who awaits for high-bouncing ball and then one-touches it into place. Seattle, 3-1. Fifth of the season for 253.
Attendance: 16,416. Second half: ... has just begun.
Halftime: Seattle, 2-1. Wild half. Martins gets two goals and a red card. Both teams playing with 10 men. Chicago scored on its only shot on target. Seattle had three ... all by Oba.
40' Fire gets one back from Harrison Shipp just as I was mentally shoveling dirt in their faces. Sounders, 2-1. Martins picks up yellow card, and now teams both playing with 10 men.
39' Oba draw a PK and hits his own PK -- which is rare -- making it 2-0 with his eighth of the season. The foul also drew a second yellow on Jhon Kennedy Hurtado, so Sounders now two goals up and playing with a man advantage.
31' GOAL Seattle. Obafemi Martins turns and fires inside the area. His seventh of the season. Sounders, 1-0.
First seven minutes: Eventful start for Martins. Nasty knockdown. Rolls ball across open goalmouth. Yellow card.
First kick: ... has been struck. Sounders and Fire under way. Seattle in rave/rave; Fire in red/red.
Lineups: For Sounders: Sounders starters> GK Frei, D Evans, Marshall, Anibaba, Gonzalez, M Neagle, Alonso, Pineda, Pappa, F Barrett, Martins. Reserves: Substitutes: Hahnemann, Scott, Azira, Kovar, Okoli, Cooper, Weaver.
For Fire: Johnson; Palmer, Hurtado, Soumare, Segares; Ward, Larentowicz ©, Ritter, Joya; Shipp, Amarikwa