The Philadelphia Union and Sporting Kansas City advanced to the U.S. Open Cup final after winning their respective semis on Wednesday.
Philadelphia, who won a draw to determine home-away priority before the semifinals were played, will serve as hosts for the Sept. 30 event.
Finalists last year, Philly extinguished the Chicago Fire's Open Cup hopes with a 1-0 victory at PPL Park.
Prolific USOC goalscorer Sebastien Le Toux netted the lone goal for the Union in the 74th minute, dribbling inside before unleashing a low, left-footed shot just inside Sean Johnson's post.
In the second semi, Sporting Kansas City broke a 1-1 second-half deadlock with two late tallies for a 3-1 victory over Real Salt Lake.
Soni Mustivar cancelled out Olmes Garcia's opener in the 35th minute before the teams headed in for the break.
Sporting snatched the lead 10 minutes from time when Benny Feilhaber fired into an empty net after a fine solo run from Dom Dwyer ended with his left-footed shot rebounding off the post and into the SKC No. 10's path.
Krisztian Nemeth then secured their place in the final five minutes later with a right-footed shot from the center of the box before Garcia was shown a straight red in second-half stoppage time.