Perry Kitchen broke a 4-4 tie in the 79th minute and DC United beat Real Salt Lake 6-4.
The 10 goals fell one short of the MLS single-game record.
Kitchen's header, off of a long service from Taylor Kemp, beat Jeff Attinella for the difference-maker. Nick Deleon's left-footed blast from way outside provided insurance six minutes later.
The teams combined for seven goals in the second half, one short of the record for most goals in a half.
Real Salt Lake jumped ahead 2-0 on goals by Joao Plata and...
Philadelphia Union midfielder Vincent Nogueira will be sidelined for at least a month.
Nogueira injured his right quad in Sunday's loss to D.C. United and has confirmed he will be out until September.
"It's a bad thing for me," Nogueira said. "I started to feel very healthy and it was a very good thing to be on the field, and now I have to stop for three weeks."
Nogueira has scored four times since the last week of May.
He is one of only five MLS players who have both an on-target shooting percentage...
The Philadelphia Union have signed Swiss international and Bundesliga veteran Tranquillo Barnetta on a free transfer using targeted allocation money.