Roy lived up to it, leading all rookies with averages of 16.8 points, 4.0 assists and 35.4 minutes in 57 games, and on Wednesday he was awarded the NBA's Eddie Gottlieb Trophy.
He received 127 out of 128 first-place votes (638 points) from a panel of sports writers and broadcasters. Toronto's Andrea Bargnani finished second with 264 points, and Memphis' Rudy Gay was third with 93 points.
"It's rare to see a rookie step in, assume a leadership role and become a go-to guy as Brandon did this past season," Trail Blazers coach Nate McMillan said. "Brandon is a phenomenal young talent and has a chance to become a very special player in this league."
Roy is the third Trail Blazer to win the award, joining Geoff Petrie (1970-71) and Sidney Wicks (1971-72).
The Blazers finished 32-50, with 11 more wins than in the previous season, but they failed to make the playoffs for the fourth straight year.
Roy was the Pacific-10 Conference's Player of the Year his senior season at Washington. He was drafted with the sixth overall pick by the Minnesota Timberwolves, then traded to Portland for the draft rights to Randy Foye.
The 6-foot-6 guard was honored as the West's Rookie of the Month in January, February and March. He also made the All-Star game's rookie squad. He scored at least 20 points 16 times, including a career-high 29 against Utah on April 4.
"This is a proud day for the city, the franchise, and Brandon, whose performance this past season speaks volumes to the direction we're headed as a franchise," Blazers general manager Kevin Pritchard said. "Both on and off the court, Brandon has demonstrated the maturity and poise of a veteran."
In his NBA debut Nov. 1 in his hometown of Seattle, Roy scored 20 points. He followed that with a 19-point game at Golden State.
"I love Brandon Roy. I love his game. He's so smooth and carefree. It seems like he never turns the ball over," Denver's Carmelo Anthony said earlier this season. "He sure doesn't seem like a rookie in this league. He's going to be The One in Portland."