The Columbus Crew came out on top against New York City FC 4-3 on aggregate despite losing the second leg 2-0 at Yankee Stadium on Sunday.
Trailing 4-1 on aggregate after the first leg in Columbus, Patrick Vieira's team got just the start it needed when Rodney Wallace was toppled in the penalty area by Frederic Brillant and David Villa slotted home the ensuing spot kick to make it 1-0.
There were nervy moments in the opening half for New York keeper Sean Johnson, a questionable punch fell to Federico Higuain in the area and a miscommunication with his defense almost saw a headed back pass find its way into his net.
Maxi Moralez's pinpoint cutback set Villa up just before half-time, but the Spaniard couldn't quite get a boot on pass before it was seemingly handled by Mohammed Abu in the area with no penalty given.
The host side clawed back one of the two goals it needed early in the second half when Crew defender Jonathan Mensah redirected Andraz Struna's shot into his own net to cut Columbus' aggregate lead to 4-3.
The chances came fast and furious after that for NYCFC, Moralez heading wide at the back post before Jack Harrison shot tamely at Zack Steffen in the Columbus goal and Wallace smashing one off the post from very close range.
Kekuta Manneh could have put it away just before the 90-minute mark, but his left-footed shot from close range smashed into the side netting to keep New York's hopes alive.
A flurry by NYCFC in stoppage time came up empty as the Crew hung on to eliminate the second-seed in the East and keep its MLS Cup dream alive.