UCLA freshman point guard Lonzo Ball had a double-double with 18 points and 11 assists to lead No. 14 UCLA past Portland 99-77 Thursday in a quarterfinal game of the Wooden Legacy at Titan Gym in Fullerton, Calif.

The Bruins improved to 5-0 behind a balanced scoring effort. Other than Ball, scorers in double figures included center Thomas Welsh (16 points), forward T.J. Leaf (14) and guards Isaac Hamilton (16), Aaron Holiday (14) and Bryce Alford (13).

UCLA will face Nebraska in a Wooden Legacy semifinal Friday in Fullerton. The Cornhuskers (4-0) beat Dayton 80-78 on Thursday. The final will be played Sunday in Anaheim, Calif.

"Our guys are playing well together, and that shows our assist-to-turnover ratio as a whole team," UCLA coach Steve Alford said about the Bruins' 29-to-11 ratio. "Our goal is to get at least 24 assists and limit the turnovers to 12. We exceeded that on both ends in this game."

Portland (3-1) was led by guard Jazz Johnson's career-high 25 points on 9-of-16 shooting from the field. Pilots guard D'Marques Tyson added 16 points.

UCLA outscored Portland 17-4 to start the second half to take control of the game with a 62-41 lead with 15:58 left in the second half. Ball sank two 3-pointers in the game-turning run right after halftime.

Welsh also established a presence inside, making two baskets in that stretch. He sank 8 of 10 shots from the field and tallied a game-high 10 rebounds. Leaf had nine rebounds, though the Bruins finished with just a 40-37 edge on the boards.

"UCLA has so many weapons, they can beat you inside and outside," said Portland coach Terry Porter, a former NBA player. "It was good for our guys to go up against a team like this. It was a good learning experience to see the kind of level of play we aspire to reach."

UCLA hit 54.5 percent of its shots from the floor, including 14 of 29 3-point attempts. Portland made 37.7 percent of its field-goal attempts, including 14 of 32 from long distance.

The Bruins are averaging 104.4 points in their first five games, topping 100 points three times. They have made 54 of 117 attempts from 3-point range (46.2 percent).

Ball was 4 of 7 from 3-point range against Portland while Hamilton was 4 of 9. Ball and Holiday combined for 16 assists with only three turnovers.

"How we take care of the ball begins with our point guards, and we can't ask for anything more from Lonzo and Aaron," Alford said. "They dictate how we play, and so far they have been impeccable on how they attacked the opposing defenses."

Portland faces Dayton in a consolation-bracket game Friday in Fullerton.

NOTES: Earlier this month, G Lonzo Ball and F T.J. Leaf became the fourth and fifth players at UCLA in the past 25 seasons to record double-doubles in their first games as freshmen. They joined a list that includes Charles O'Bannon (Nov. 27, 1993), Kevin Love (Nov. 8, 2007) and Kyle Anderson (Nov. 9, 2012). ... Former USC interim head coach Bob Cantu, most recently a UTEP assistant, is an assistant under Terry Porter at Portland ... UCLA senior G Bryce Alford entered this season as the only returning player in a Power 5 conference who averaged at least 16.0 points, 5.0 assists and 3.0 rebounds per game last year.