A goalmouth scramble ensured the deadlock was broken nine minutes later when Deshorn Brown took advantage of some hesitant Portland defending from a corner to tap home from close range.
The Timbers applied pressure midway through the first half and were inches away from levelling the scores when Liam Ridgewell, who was making his first start for the club, headed wide of the post.
Ricketts then made a vital save just moments before the break to deny Dillon Powers and prevent the hosts from falling further behind.
Colorado were left frustrated once again in the 55th minute as Ricketts continued to excel under pressure by getting a strong hand on Dillon Serna's strike.
The Timbers had their tails up and just five minutes after the equaliser they were level, Diego Valeri with the finish to put the hosts ahead.
Having trailed for the majority of the match, the home side were happy to retain the one-goal lead for the final 10 minutes and see the game out for the three points.