D.C. United and the Chicago Fire are both locked into playoff spots, but numerous scenarios could see them finish with various seeds in the Eastern Conference.
Both teams are focused simply on winning, and the No. 2 spot is theirs.
Separated by one point in the standings, the Fire will host United in Saturday's regular-season finale.
A draw or loss could drop Chicago (17-11-5) to fourth or fifth, subjecting it to a spot in the East's one-game knockout match on Wednesday. A draw is good enough to give D.C. the second seed, but a loss and a New York win against Philadelphia would see United finish fourth.
Few MLS teams are playing as well as D.C., which is riding a six-game unbeaten streak (5-0-1) and clinched the club's first playoff berth since 2007 with last Saturday's 3-2 win over Columbus. The unbeaten run surprisingly started immediately following a season-ending knee injury to captain and 2011 MLS Most Valuable Player Dwayne De Rosario.
Numerous players have picked up the slack in the absence of De Rosario, who could return if D.C. makes a deep playoff run. Seven players have accounted for nine goals, with Chris Pontius and Lewis Neal each scoring twice.
"We have grown closer since Dwayne went down, and it isn't a negative towards Dwayne, it was survival," said coach Ben Olsen, who played on United's last playoff team. "Everybody understands we have to be a real team now. We have to commit to each other and bail each other out. I think that's slowly, over this six-week period has got us to the point we are today."
The Fire, meanwhile, are reeling. With last Saturday's 1-0 defeat at New England, Chicago lost for the third time in four matches following a 7-1-0 run. The only blemish in that stretch was a 4-2 setback in D.C. on Aug. 22. That was the first time all season the Fire allowed more than two goals, and the loss still stings.
"Everyone is excited to play a very important game," Chicago striker Sherjill MacDonald told the team's official website. "We remember the game there in August and it's still very fresh in my mind. The last time we were in D.C. they were very sharp and aggressive. We've wiped the slate clean. We feel ready for Saturday."
The Fire, winners of six of seven at home, should benefit from the returns of midfielder Pavel Pardo, who missed six games with a calf injury, and forward Guillermo Franco, who served a two-game MLS suspension.