New England Revolution have moved level on points with New York Red Bulls and DC United at the top of the Eastern Conference after Teal Bunbury's goal saw them beat Philadelphia Union.
The hosts thought they had taken the lead early on when Fernando Aristeguieta saw his close-range shot turned onto the crossbar by Bobby Shuttleworth, although replays suggest that the Venezuelan forward was in an offside position.
Union took the lead three minutes before half time when Christian Maidana's dipping free kick crept into the net off the right-hand post.
New England almost got back on level terms within moments of falling behind when Kelyn Rowe's sweetly-struck volley drifted wide of John McCarthy's goal.
However, they did equalise midway through the second period when substitute Bunbury teed up Charlie Davies, whose shot proved too much for McCarthy.
Bunbury then gave the Revolution the lead with 14 minutes left as he was allowed to run at the Union goal before his low shot found the back of the net.
New England almost surrendered their advantage within minutes when they needed goalline blocks to keep out efforts from Aristeguieta and Maurice Edu in quick succession.
New England were able to hold on for victory and trail Eastern Conference leaders New York Red Bulls on goal difference.
