The Ecuadorian struck early in the first half to continue the Timbers' miserable campaign.
The home team got off to a flying start, thanks to a great run and cross by Ryan Smith. The Englishman got the better of two Portland defenders before squaring across the box for an easy finish on the back-post by Bolanos. The goal was the Ecuadorian's first in Major League Soccer.
The Goats had most of the game's goalscoring opportunites, but couldn't put a second past Troy Perkins. Portland rarely threatened Dan Kennedy's goal, and the All-Star goalkeeper saw his shutout streak move past 300 minutes.
With the win, the Goats extended their unbeaten run to four games, and moved up to sixth in the Western Conference. The Timbers continue their difficult season, as they stay tied with FC Dallas for last in the West.
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