The 27-year-old played in two friendlies after being offered a chance to impress by former United States Under-23 coach Caleb Porter, now a coach with the Timbers.
However, Porter confirmed on Oregonlive: "Freddy is no longer with us. He had two weeks and we were up front and honest with him about where we're at. More than anything, you look at the depth, there's just not going to be a spot."
Adu signed a professional contract with DC United aged just 14 in 2004 but now finds himself without a club after leaving American second-tier side Tampa Bay Rowdies last year.
His career stalled following his early promise, with stints in the Portuguese, Serbian, Finnish, Turkish, Brazilian, French and Greek leagues.body check tags ::