Injected with new life in the quest to earn their first-ever MLS playoff berth and claiming to have learned a lesson from their disappointing play in the loss to Houston, the Portland Timbers insist they will not let another chance slip away without a fight.

"We do need to become a little more physical, a little tougher, a little grittier," Portland goalkeeper Troy Perkins said. "You step onto the battlefield…you've got to become that nasty person, that mean person."

That's right, Portland fans. The Timbers, never accused of being a team with an ornery attitude, realize they may have to get down, get dirty, even get beastly to win a big, playoff-like game such as the one at D.C. United Wednesday.

"We need to be more physical. That's for sure," Portland coach John Spencer said. "We need to stand up to the physical battle."

That was the Timbers' revelation coming off a demoralizing loss to Houston in their final home game of the season that damaged their playoff hopes. However, losses by New York and D.C. United during the weekend revived the Timbers' playoff aspirations.

"We've been given a second chance now," Spencer said. "But we need to start taking care of our own business by winning games."

Even before the weekend results, the Timbers needed to win the game at D.C United Wednesday - and at Real Salt Lake Saturday in their final regular season game - to put themselves in position to grab a playoff spot should other teams stumble.

"We can put pressure on New York," Spencer said. "It's up to us to play well and get a good result and make New York have to beat Philadelphia (on Thursday)."

Facing another big game - on the road this time - the Timbers know they must approach the game differently against D.C. United to affect the outcome of the game compared to the disappointing performance against Houston. The Timbers allowed the Dynamo to shove them around Jeld-Wen Field as if they were the skinny little student cowering at the sight of an angry bully in elementary school.

"We need to say, if (our game plan) is not going to work, then we're just going to throw the gloves off and we'll go bare knuckles to bare knuckles and fight this out," Perkins said.

Perhaps the play the encapsulated the game against Houston was when Dynamo midfielder Danny Cruz leveled Portland defender Mike Chabala with a hit that was borderline dirty (Cruz received a yellow card). While Chabala laid on the turf, what was surprising was no Portland player challenged Cruz in defense of a fallen teammate. No nose-to-nose trash talking. No chest-to-chest confrontation. No Portland finger slamming into Cruz's chest.

Nothing.

"It was disappointing," Chabala said. "If it had happened to somebody else on my team, I'm getting in somebody's face. Regardless whether it's (a teammate) I've known for two weeks or two years…I would've been right there in the middle of it sticking my face in somebody else's face."

Perkins suggested that maybe the Timbers were so shocked that Cruz didn't receive a red card and ejection that they didn't react at all.

"Maybe it was a little naiveness and inexperience in not going after the guy and saying, 'That's not acceptable,' " Perkins said. "(The toughness) is something we've seen sometimes during the season, but we haven't seen enough of it."

Are the Timbers too nice - too soft - for the rough and tumble world of playoff soccer? Many coaches have talked about the Timbers' physical play throughout the season, but when the Timbers needed to match the Dynamo's rugged style of play, the young group didn't respond.

"If you're playing a physical team, you have to try and win the physical battles," Spencer said. "(Friday) night, we were trying to create and it wasn't that type of game. It was a game where we had to fight tooth and nail for every inch on the field.

"We were caught off-guard by it. I don't know why, I mentioned it in the pre-game (talk), the type of mentality that Houston has."

Both Perkins and Chabala, veterans who competed in playoff games, said the Timbers had better approach and play the game against D.C. United - the Timbers lost 3-2 to D.C. United at home May 29 - with a much more aggressive attitude and passion than they did against Houston.

"You can't perform and play the same as you do in the middle of the season as you do in these games. The guys that are older need to make sure that the atmosphere does change and we do that within ourselves," Chabala said. "If we can roll up our sleeves and fight a little bit…I think if we come out there with a little chip on our shoulder, I think you will see a different club."

Notes: Midfielder Sal Zizzo could be lost for the remainder of the season after suffering a left knee injury. Zizzo injured the knee during the first half of the Timbers' game against Houston Friday and will not play Wednesday.

-- Geoffrey C. Arnold; follow him on Twitter.