The shooting guard was traded from the Oregon outfit down the West Coast in February, just months after signing a mammoth new five-year deal to stay with them.
Facing off against his former side, Powell posted a 32-point performance off the bench, with 22 coming in the final quarter alone, to take the team to 13-9 for the season.
Lue acknowledged the 29-year-old was likely to be fired up by the chance to impress against the Trail Blazers, and was more than happy to reap the rewards.
"When you get traded from somewhere, you want to play well against them," Lue stated after Powell connected on four of his five three-point attempts.
"I thought he was a little too excited in the first half - we are always going to stay with our guys and he had 24 points in the second half, really attacking the basket.
"He was getting to the paint and getting to the free-throw line.
"He's been playing great for about the last three to four weeks."
Powell, a former NBA champion during his time with the Toronto Raptors, is looking to help the Clippers bounce back after the team missed the playoffs by coming up short in the play-in tournament last term.
The Clippers are fifth in the Western Conference, two places above Portland, who dropped to 11-10.