FC Dallas won its last meeting with the Portland Timbers by five goals without Brek Shea.

It's unclear if Shea will finally return for Dallas when it goes on the road to try to hand the Timbers a sixth straight loss Sunday.

Shea has not seen action since an argument with coach Schellas Hyndman after he was taken out of a 2-1 loss at San Jose on July 18. The 22-year-old star midfielder scored 11 goals last season but has been held to three this year.

Hyndman has benched Shea for two straight games, including last Saturday's 1-0 defeat to Los Angeles.

"What Brek has been doing is trying to live up to expectations of everyone else and himself," Hyndman told Dallas' official website. "And when the game doesn't go well for him, it gets really frustrating and the pressure really mounts."

The first contest Shea missed was a 5-0 home victory over Portland (5-12-4) on July 21 behind Jackson's goal and two assists. That result has Dallas (5-11-7) wary of a backlash two weeks later.

"I think we can't be overconfident, they're still a good team," FC Dallas defender Matt Hedges said. "We beat 'em 5-0 so they're going to want to come out and get revenge on us so we have to be sharp all the time."

That defeat was clearly Portland's worst effort under interim coach Gavin Wilkinson, who called it "unacceptable."

"I think when we played Dallas, we were poor and they were very good and it created a bigger difference," Wilkinson said. "When we play this Sunday, we've got to be very good and we'll see what we're up against."

The Timbers have been outscored 15-3 during their losing streak, with the last four games coming since Wilkinson took over for John Spencer.

Wilkinson made six changes last Saturday and the effort was better in the Timbers' 1-0 loss to Chivas USA. Portland was happy with its response after finishing with a 19-8 edge in shots.

"The match against Chivas, we had a lot of opportunities and hopefully we create the same opportunities against Dallas and put them away this time," midfielder Darlington Nagbe said.

Portland has not scored in 292 minutes. The Timbers own the longest goal drought in MLS this season at 339 from April 21-May 20.

One player looking forward to this matchup is Dallas midfielder James Marcelin, who was waived April 25 by Portland. Marcelin logged 16 minutes in the last matchup with the Timbers and is anxious for his return to Jeld-Wen Field.

"I'm just excited to go back and play them again," Marcelin said. "When you play for Portland, you always know a lot of fans are going to come support you."

Dallas is 1-8-1 on the road while Portland is 5-4-2 at home. The second-year Timbers took their lone home matchup between these teams 3-2 on April 17, 2011, before Dallas outscored Portland 10-1 while going 2-0-1 in the next three.