Steve Alford says a lack of depth has been a big reason why UCLA has struggled on defense

It happened again.

Two years after UCLA men’s basketball coach Steve Alford vowed in a letter to fans that his team’s poor defensive showing “can never happen again,” a regrettable chapter in Bruins history has repeated itself.

The Bruins’ adjusted defensive efficiency stands at No. 122 in the nation, according to the metrics of Ken Pomeroy, four spots worse than it was during a 2015-16 season that ended without an appearance in the NCAA tournament.

UCLA’s current postseason fate remains uncertain heading into its final regular-season game against USC on Saturday at Galen Center. The Bruins (19-10, 10-7 Pac-12 Conference) are tied with Utah for fourth place in the conference and are widely considered to be on the bubble of advancing to the NCAA tournament.

The irony is that Alford had expected this team to be strong defensively. Then the Bruins went to China in November and three players were lost for the season after stealing merchandise from upscale stores at a mall.

“That’s a lot of athleticism and length to lose in your defense overnight,” Alford said Wednesday. “It’s not an excuse, but you’re asking me what happened [and] defensively we took on a whole ’nother look because we don’t have the depth. We couldn’t extend pressure, basically we weren’t going to play beyond eight guys.”

The Bruins reined in their defense without Jalen Hill and Cody Riley, two long and athletic forwards, and LiAngelo Ball, a 6-foot-6 shooting guard whose loss of 20 pounds had made him increasingly mobile. Hill and Riley were suspended for the season in the wake of the shoplifting incident and Ball left to play for a professional team in Lithuania.

UCLA’s resulting defensive problems are not a result of neglect; Alford said his team “puts three times more energy in practice at the defensive end than what we have at the offensive end. … It’s not so much hitting the panic button as [saying], ‘Guys, here’s where we’re a little lax in, we’ve just got to get a little tougher-minded in how we concentrate and how we execute.’ ”

The list of issues has been lengthy. The Bruins have largely failed to stop dribble penetration or defend the three-point line. They have been slow to rotate at times and over-helped at others. Mixing in a 3-2 zone defense has not appreciably solved anything for a team that is giving up 76.4 points per game, ranking 10th in the Pac-12.

Alford’s teams were known for strong defense during coaching stops at New Mexico and Iowa. The Lobos ranked No. 15 and No. 16 nationally in adjusted defensive efficiency under Alford in his last two seasons there, and the Hawkeyes led the country in that category during the 2005-06 season.

The Bruins have gotten progressively worse in defensive efficiency under Alford since ranking No. 37 during his first season in 2013-14; they ranked No. 66 in 2014-15 and No. 118 in 2015-16 before a slight uptick to No. 85 last season. Alford pinned his team’s defensive struggles from two seasons ago on a recruiting miss involving guard Jaylen Brown, who picked California over UCLA, and graduate transfer Jon Octeus being denied admission, leaving the roster woefully thin.

“You couldn’t look at your bench and say, ‘OK, let’s motivate by sitting you and playing somebody else,’ ” Alford said. “You couldn’t do that because there was nobody else to go to.”

Alford acknowledged that last season’s team favored offense over defense because it was so elite in the former category thanks to a talented cast led by point guard Lonzo Ball.

“Different teams have different identities,” Alford said, “and that team’s was, we outscore you.”

UCLA advanced to an NCAA tournament regional semifinal three times during Alford’s first four seasons, something that only a handful of other teams in the nation could claim over the same stretch. Alford disagreed with the notion that last season was a disappointment because the Bruins did not go further with so much talent.

“Getting to the Sweet 16 is hard to do in this era now; I think you’re looking at a whole different era,” Alford said, “and so I do think that is an accomplishment that kind of gets thrown under the rug but a lot of teams would like to be getting to the Sweet 16.”

The Bruins won the Pac-12 tournament during Alford’s first season but are assured of going a fifth consecutive season without a regular-season conference title under the coach who has compiled a 115-55 record. Alford’s winning percentage of 67.6% at UCLA is worse than predecessors Ben Howland (73.7%) and Steve Lavin (70.8%) through their first five seasons.

While UCLA athletic director Dan Guerrero said in January that he expected a program to be “clicking on all cylinders” by its fifth year under a coach, Alford said he used a different metric to evaluate his results.

“I don’t really look at it where we are at Year 2, 3, 4, 5; it’s just, are we doing everything we can with what we have?” Alford said. “I feel like the staff has worked extremely hard, I think the players have worked extremely hard. … We would have liked to have won a [Pac-12] championship, but with everything that’s happened and everything that’s transpired, these guys have worked awfully hard, they’ve done a lot of good things and now we’ve got to wait and see how we finish here.”

ben.bolch@latimes.com

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