Time: 7:30 p.m. EDT
Venue: PPL Park, Chester, Pa.
TV: Comcast SportsNet (J.P. Dellacamera, Alejandro Moreno and Heather Mitts, with Tony Limarzi, Peter Pappas and Ian Munro at the on-site studio desk)
You already about Los Angeles' big money men, Robbie Keane and Landon Donovan. With Keane expected to return from injury tonight, it's a safe bet that he'll command much of the spotlight.
But the Galaxy's biggest strength is its depth of talent, and you'll likely see why tonight. Mike Magee is second to Jack McInerney in the scoring charts, while Jose Villareal and Gyasi Zardes are two of the hottest young prospects in MLS.
This game will be a huge test for a Union team that has quietly established itself as one of MLS' toughest to beat. It will also be the latest chapter in a series of games that has seen plenty of dramatic moments. Philadelphia's stunning 2-1 win at the Home Depot Center last year was just one example.
So buckle up for what could be a wild night at PPL Park. Let's find out which team will make the bigger statement.
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Philadelphia Union (4-1-3-2, left to right)
Goalkeeper: Zac MacMath
Defenders: Raymon Gaddis, Bakary Soumaré, Amobi Okugo, Sheanon Williams
Midfielders: Brian Carroll; Keon Daniel, Kléberson, Danny Cruz
Forwards: Sébastien Le Toux, Jack McInerney
Bench: GK Chris Konopka; D Chris Albright; Ms Michael Farfan, Roger Torres; Fs Conor Casey, Antoine Hoppenot, Aaron Wheeler
Los Angeles Galaxy (4-4-2, left to right)
Goalkeeper: Carlo Cudicini
Defenders: Todd Dunivant, Tommy Meyer, Omar González, A.J. DeLaGarza
Midfielders: Mike Magee, Marcelo Sarvas, Juninho, Landon Donovan
Forwards: Jose Villareal, Robbie Keane
Bench: GK Brian Rowe; Ds Greg Cochrane, Sean Franklin, Leonardo; Ms Rafael Garcia, Hector Jimenez; F Charlie Rugg
Referee: Ismail Elfath
Linesmen: Craig Lowry (bench side), James Conlee (far side)
Fourth Official: Chris Penso