Porter didn't want the Timbers to get too caught up in the streak that everything that comes with it, so he gave them free rein against the Goats.
''I told them to go out. Don't think. Be free. Play,'' Porter said following the match.
Portland's undefeated streak is an ongoing franchise-best for the Timbers, who joined Major League Soccer in 2011. Portland (4-1-6) suffered its lone loss back on March 9 when the team fell 2-1 at home to Montreal.
The victory pulls Portland even for the MLS lead with Dallas FC, which also has not lost in nine matches.
Chivas (3-5-2) is in last place in the Western Conference. They have not won since a 2-1 victory over Vancouver on March 30.
''My team is running. My team is fighting. My team is giving the effort,'' said Chivas coach Jose Luis Sanchez Sola, who is known as Chelis. ''It's just not enough.''
The match was marred in the 86th minute when Chivas midfielder Mario de Luna pushed a ball boy after the kid picked up an out-of-bounds ball. De Luna was yellow carded, and because of a previous yellow, he'll miss next Sunday's match against Real Salt Lake.
Afterward, both Porter and Chelis shook the ball boy's hand.
The Goats were without starting goalkeeper and captain Dan Kennedy because of a red card in last week's loss to Sporting KC. Patrick McLain, in his MLS debut, allowed two goals after Kennedy was sent off in the 4-0 Chivas loss.
McLain made his first league start against the Timbers while backup goalkeeper Tim Melia continues to recover from a lower back injury.
McLain leapt with his arms outstretched but couldn't stop Wallace's left-footed rocket from just outside the left corner of the box in the 34th minute. Wallace's third goal of the season came off a pass from Ryan Johnson on a fast break.
The Timbers made it 2-0 when a wide-open Valeri beat McLain in the 70th minute. Valeri blew kisses to the fans following the goal.
Johnson's fourth goal of the season came in the 90th minute when his low kick skirted past several defenders and the reach of McClain.
It was Portland goal keeper Donovan Ricketts' fourth clean sheet of the season.
''The chemistry is out there. We're all connected,'' Wallace said. ''I think every single guy on this team - whether they're starting or not - is giving their all.''
Portland visits Cascadia Cup rival Vancouver next Saturday.
Chivas was also without midfielder Carlos Alvarez, who was suspended two games and fined an undisclosed amount by the MLS for 'violent conduct' during the loss to Sporting KC.
Alvarez, penalized for kicking the ball at Peterson Joseph's head, will also miss the team's match against Real Salt Lake on May 19.
Earlier this week, Chivas traded Juan Agudelo to the New England Revolution in exchange for allocation money. The forward had two goals this season for the Goats.
Chivas USA won all three meetings with the Timbers last season.
The Timbers Army supporters group coordinated for a fan display of a rainbow flag, unfurling a banner that said ''Pride Not Prejudice'' in recognition of International Day Against Homophobia this May 17.
Attendance for the match was announced at 20,674, the Timbers' 40th straight sellout.
- Sports & Recreation
- Chivas USA
- Diego Valeri