No. 4 UCLA surpassed its win total of last season with an 89-75 win Sunday over Stanford behind guard Lonzo Ball's 21 points, but coach Steve Alford is not about to term everything a success to this point.

"This season's a journey," Alford said after the game at Pauley Pavilion in Los Angeles. "We have to enjoy winning. It's not about margins. It's about winning.

"I'm not going to get frustrated with a 14-point win. Our guys know even though we're 16-1 that we have a big ceiling to grow and get better."

The fourth-ranked Bruins finished 15-17 overall a season ago. In addition to being 16-1 now, they are tied atop the Pac-12 standings with Oregon and Arizona with a 4-0 record.

Ball made 4 of 5 attempts from 3-point range and finished with eight assists and six rebounds. Guard Bryce Alford, who also made 4 of 5 shots from beyond the arc, added 17 points for the Bruins while forward T.J. Leaf had 15 points, 10 rebounds and six assists and guard Isaac Hamilton had 15 points.

Stanford (8-8, 0-4) played its second consecutive game without leading scorer and rebounder Travis Reid, a junior forward who suffered a shoulder injury in practice last week. He is out indefinitely.

The Cardinal was led by forward Michael Humphrey's career-high 27 points and 14 rebounds before he fouled out with 1:56 left in the game. Guard Robert Cartwright also had a career-high marks in three categories -- 18 points with nine assists and five rebounds.

"Mike did not play a perfect game, but I liked his energy and his consistency," Stanford coach Jerod Haase said. "This whole thing is a process individually and collectively. We can talk about points and assists with Robert, but it does not mean anything.

"What's important is the leadership. The team is not going to run well until we have a fundamental leader out there. For the most part tonight, I thought he ran the point really well."

UCLA, which built a 48-30 lead at halftime, guarded against a letdown similar to what happened against Cal at Pauley Pavilion on Thursday.

The Bruins led 44-24 at halftime against the Golden Bears and built a 24-point lead in the second half before Cal cut the lead to five points with less than a minute remaining. The Bruins eventually won 81-71.

Stanford cut UCLA's lead to 59-48 on an 11-2 run capped a tip-in by center Josh Sharma with 13:38 left in regulation. The Bruins responded with an 8-2 spurt that included 3-pointers by Ball and guard Aaron Holiday.

The Cardinal could not cut more into the lead after trailing 71-59 with 9:38 remaining.

"I get it that we judge our performance on the scoreboard, but I was proud of the way the guys executed and competed today," said Haase, in his first year as Stanford's head coach.

Alford said the lapse this time came down to allowing Stanford too many offensive rebounds. The Cardinal tallied 16 offensive rebounds and outscored the Bruins 16-8 on second-chance points.

UCLA also made only 16 of its 25 free-throw attempts.

"If we make 20 or 22 free throws, it's a wider margin," Alford said. "There's not a better team with a transition offense than what we have (averaging 92.8 points a game). I told the guys if we can take those 16 offensive rebounds and cut it down to eight, that's eight more times we're off and running."

Behind 15 points by Ball in the first half, on 6-of-8 shooting from the field, UCLA never trailed against Stanford. Ball and Alford each made 3 of 4 shots from 3-point range in the first half to fuel a 57.1 percent shooting performance from there in the first half.

The Cardinal finished shooting 37.8 percent from the field, including 29.4 percent from 3-point range. UCLA shot 50 percent from the field and 55 percent from beyond the arc. The Bruins made 11 3-pointers.

NOTES: Stanford faced three consecutive teams ranked in the Associated Press national poll for the first time in 15 seasons. The Cardinal lost to No. 18 Arizona last week and No. 25 USC on Thursday and No. 4 UCLA on Sunday. ... UCLA senior G Bryce Alford ranked No. 12 nationally among all active players in career points (1,633) entering this weekend. He is the only player in the top 210 who competes in a Power 5 conference. ... UCLA and Stanford do not play again in the regular season due to the Pac-12's unbalanced scheduling with 12 teams playing 18 conference games each. The teams played only once last season as well with Stanford winning 79-70 in Palo Alto, Calif.