John Hackworth's Philadelphia Union are 12 points out of a playoff spot, but a win on Sunday can cut that deficit to single digits.
Frank Klopas is quietly guiding his Chicago side to a very good season. His group is now on 35 points, with a 10-7-5 record. They are just 5 points behind conference leaders Houston and Kansas City.
This will be the second meeting between the Union and Fire in 2012. Back in March, Chicago got the best of Philadelphia in a 1-0 shutout at Toyota Park. Dominic Oduro's 28th minute goal held up, as backup goalkeeper Paolo Tornaghi made a pair of spectacular second half saves.
Philadelphia is 2-2-1 all time against Chicago. The Union have won both matches against the Fire at PPL Park.
It's been wildly inconsistent this year. Klopas' team has scored just 25 goals this year, the lowest number amongst all teams currently in playoff position.
Talented midfielder Marco Pappa is the team leader with 6 goals. MLS fans should be familiar with his technical skill on the ball and his ability to create plays in the final third.
The aforementioned Oduro is second on the team with 5 goals. The speedy striker isn't having the year he had in 2011, but he's always a threat to get behind opposing center halves and score.
Beyond Oduro and Pappa, there's been a bit of a shuffle in the Chicago attack. Sebastien Grazzini was the focus of a mid-season contract issue. The Argentine midfielder eventually did reach an agreement to stay in Chicago, but has since traveled home to attend to personal matters. The team also brought back former standout Chris Rolfe, who spent the last two seasons with Danish side Aalborg. The Fire also acquired designated player Alvaro Fernandez from Seattle just last month. The Uruguay international made his debut in the recent 2-1 victory over Toronto.
For the most part, Klopas has stayed with a typical 4-2-3-1 formation this year. Veteran midfielders Pavel Pardo and Logan Pause will sit behind the four attackers and attempt to control the flow of the game while guarding the backline. Pause and Pardo have played nearly 1,000 combined games at the professional level, so there's certainly no lack of experience in that department.
On the backline, it seems like Chicago can now rely on Arne Friedrich as a regular starter. The oft-injured former Germany international is providing stability to a defense that has played well despite a number of personnel changes.
Veteran Cory Gibbs underwent successful knee surgery in April, and has been out of action ever since.
But rookie Austin Berry has been a revelation on the backline. The Louisville product now has 16 starts in his debut year. And, go figure, he's also third on the team with 3 goals scored. He's a six foot two guy with great aerial ability.
Second year man Jalil Anibaba has re-settled into his more typical right back role. That's a spot where Dan Gargan is best used as well. Gonzalo Segares is mostly consistent in his performances at left back.
First choice Goalkeeper Sean Johnson is quietly putting together another solid season in net.
Keys to the Game
A lot has changed since that late March matchup.
For starters, the Union played a 3-man defense in Chicago, with Carlos Valdes, Chris Albright, and Porfirio Lopez on the backline. Gabriel Gomez would drop deep in a hybrid M/D role, to accommodate for fullback runs up the pitch.
That was also when the Union were not playing strong soccer and were struggling to score.
Chicago has been similar to Philadelphia this season, in the sense that the defense is solid, but the offense is very inconsistent. The Fire are looking to get Fernandez situated in the starting XI, while Rolfe seems to have settled into Grazzini's vacated attacking midfield role. It's a bit of a transitional period in Chicago, but Klopas' club is coming off a good road draw with San Jose, and a 2-1 home win over an improved Toronto side.
While the 4-2-3-1 seems to be the typical shape, there's always a lot of movement in Chicago's formation. Sometimes the shape will look more like a 4-1-4-1, with Pause and Pardo picking spots to move forward. But the idea has always been about getting the ball to the four playmakers in front of the defensive midfielders.
Philadelphia has the obvious advantage at PPL Park, winning four straight league games at home. A Sunday win will bring the Union within 9 points of Chicago, and the final playoff spot in the Eastern Conference.