Philadelphia Union moved four points clear atop the MLS Eastern Conference standings following a 3-2 win over Columbus Crew on Wednesday.
After falling behind early at the Talen Energy Stadium, the Union fought back to take a 3-1 lead in the second half, before a 10-man Columbus scored a stoppage-time consolation goal.
The win extends Philadelphia's lead over New York Red Bulls and Montreal Impact to four points, but the latter has a game in hand over the Union.
Columbus went ahead in the 14th minute through Ola Kamara's acrobatic effort, but Philadelphia hit back seven minutes later thanks to Chris Pontius' fifth goal of the season.
Philadelphia took the lead 12 minutes into the second half after Vincent Nogueira found the net, before Conor Casey was shown a dubious red card after coming on just two minutes earlier.
Fabian Herbers utilised the Union's extra-man advantage to make it 3-1 in the 84th minute with a well-taken finish, but Christian Martinez scored in the closing stages to bring the difference back to one goal.
Philadelphia held on for the slender win which sees them move to a franchise-tying eight games unbeaten in MLS.
Seattle Sounders snapped a three-game losing streak thanks to a 2-0 win at DC United.
Fresh off their 1-0 win over Sporting Kansas City, DC were looking to continue their push up the standings in the east.
However, Seattle had other ideas, with two goals in the space of four minutes from Jordan Morris and Joevin Jones late in the second half sealing the win for the visitors.
Meanwhile, a first-half goal from Liam Ridgewell was enough for defending MLS Cup champions Portland Timbers to see off San Jose Earthquakes 1-0.
Former West Brom and Aston Villa defender Ridgewell scored in the 11th minute as the Timbers held on for the win, despite playing the entire second half with 10 men following Dairon Asprilla's red card.