VANCOUVER - Scoring the first goal is important in any soccer game.

Who scores first will take on even more significance when the Vancouver Whitecaps host the Portland Timbers in the second leg of the Major League Soccer Western Conference semifinal at BC Place Stadium on Sunday. 

The teams battled to a 0-0 draw in last week's opening match of the two-game, aggregate-goal playoff. With away goals serving as the tiebreaker, Portland can advance into the conference final with a draw of 1-1 or higher.

If Portland should take an early lead, the Whitecaps would have to score twice to keep their MLS championship aspirations alive.

Goals haven't come easy for the Whitecaps. They scored seven times during their final seven games of the season, but three of those came in a 3-0 victory over the Houston Dynamo. That was the final game of the season and Houston was already eliminated from the playoffs.

Midfielder Russell Teibert said the Whitecaps must show patience no matter how Sunday unfolds.

Scoring first “is crucial, but it's not the end all of the game,” he said.

“We've proven we can come back in games. We've done it before and we will do it again. It would be nice to score the first goal. It would be nice to score a goal.”

The Whitecaps failed to connect on a couple early chances against the Timbers at Providence Park. Portland seemed to have the momentum later in the game and the Whitecaps needed a great save by goaltender David Ousted and a shot off the goal post to escape with the draw.

Defender Steven Beitashour said prevention can be as important as scoring.

“You don't want to give up the first goal,” he said. “I think that might be bigger than getting the first goal. You don't want to give up the first goal because then you are chasing two.

“Also, after you get that goal, you've got to continue and not just think it's over. I think the most important thing is starting off right and playing the entire 90 minutes.”

The Whitecaps finished second in the Western Conference with a 16-13-5 record. They were 9-6-2 at home during the regular season.

Portland was third in the West at 15-11-8. Their road record of 7-8-2 was one of the best in the conference. They are 3-1-2 at BC Place over five seasons.

Portland coach Caleb Porter said his team is confident playing in Vancouver after winning four of their last five games on the road.

“We're in position,” Porter told the Timbers' website. “I don't know if we have the advantage or they have the advantage. They are at home.

“We also know we can draw and go through. That gives us a slight advantage. This team is very confident on the road. We know we can go and get a result. We are going to continue to play to win. We'll be smart, we'll be organized and we won't be reckless in how we look to get that win.”

The Whitecaps' chances will be improved with the return of a healthy Pedro Morales. The Chilean midfielder and playmaker has battled calf, hamstring and back problems the last five months. He played 15 minutes in the first game and is expected to see more time Sunday.

Morales has six goals and four assists in 23 games this year.

A crowd of around 27,500 is expected for the Whitecaps' first home playoff game.

Teibert said the Whitecaps are taking an underdog mentality into the game.

“We've been fighting all year long,” he said. “I think everybody underestimated us and didn't think we would come second in the conference and we surprised people.

“There is nothing better than proving people wrong.”

The winner of the series goes on to face either Seattle or Dallas in the Western Conference final.