Perry Kitchen also scored for DC United (4-4-3). The Washington. D.C., club has two victories and two ties in its last four MLS matches. Jack Jewsbury and Jorge Perlaza scored in the second half for Portland (5-4-2).
''We got what we deserved today, which was zero points,'' Timbers coach John Spencer said. ''We didn't deserve to get nothing from the game.''
The Timbers won their first five league matches at Jeld-Wen Field, a record for an expansion team. Portland was coming off a 1-0 victory over Columbus in its last MLS match last weekend and a 2-0 loss Wednesday night in an international exhibition against AFC Ajax of the Dutch Eredivisie.
Pontius gave United a 2-1 lead on a penalty kick in the 75th minute, firing a shot past goalkeeper Troy Perkins, who played for DC United from 2004-07 and again last season.
Pontius was awarded the kick after a handball was called on Diego Chara.
There was a flurry of activity in the final minutes. Wolff scored in the 85th minute to give United a 3-1 advantage, and Perlaza cut the margin to a goal in the 88th minute.
Jewsbury smashed a penalty kick into the left corner in the 64th minute to tie it at 1, capping a strange sequence of events where United goalkeeper Bill Hamid twice saved penalty kicks from Portland forward Kenny Cooper, but was called both times for coming off his line.
An irate Hamid charged at referee Geoff Gamble, who was working just his second MLS match, and was given a yellow card. Spencer then swapped Jewsbury for Cooper for the successful third attempt.
Cooper pleaded with Spencer to allow him to take the third kick, leading Spencer to pull him from the game. Cooper apologized to his teammates after the game.
''We had a private chat,'' Cooper said. ''Obviously, I am sorry and embarrassed with my actions. I shouldn't have put up such a fight.''
Kitchen scored in the 13th minute off a throw-in from Pontius that Blake Brettschneider deflected into the middle on a header.
United was coming off a 2-1 loss to AFC Ajax last Sunday.