The current University of Akron coach will finish the season with the Zips, then assume control of the Timbers in December.
Porter will remain the head coach at Akron through the 2012 NCAA season, and will assume his new role in December.
“Put simply, I believe Caleb Porter is the best young soccer coaching mind in the country,” said Timbers owner and president Merritt Paulson.
“He is the right fit for the Timbers on every level. We went through an exhaustive and thorough search over the last couple months where we spoke with some truly excellent candidates, but Caleb quickly emerged as the consensus target."
Porter, 37, has led the University of Akron to unprecedented success during his seven seasons at the helm. The Zips won the 2010 NCAA title and were the runners-up the season before. Porter owns the highest win percentage among active NCAA Division I coaches, with a career mark of 106-17-14 (.825).
Additionally, Porter has sent an army of talent to the MLS level, including current players Teal Bunbury, Perry Kitchen, Darren Mattocks, Darlington Nagbe, Steve Zakuani, Blair Gaven and Ben Zemanski, among others.
Porter became well known this spring for a high-profile failure, as the U.S. U23 Olympic team could not advance out of a qualifying group featuring Cuba, Canada and El Salvador, finishing in third with a 1-1-1 record.
"I am truly excited and honored to be provided this unique opportunity to coach the Portland Timbers, an organization that in a short-time has established itself as a model franchise in Major League Soccer,” said Porter.
Porter will take the helm in December from interim coach and current general manager Gavin Wilkinson, who took over for the fired John Spencer in July.
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