Bluejays freshman Jackson McAndrew, one of Tuesday’s few bright spots, missed a rushed 3-pointer and Aztecs guard Miles Byrd had just buried one on the other end to send the red half of MGM Grand Garden Arena into a frenzy.

It was a telling, emblematic stretch in the second half of the No. 21 Jays’ eventual 71-53 loss.

With a “Let’s go Aztecs!” chant roaring from the stands behind CU’s bench, McDermott walked out halfway onto the court, stared up to see a 12-point deficit, turned to walk back toward the huddle and shook his head.

“Defensively, we were out of sorts,” McDermott said, “and allowed them to create that separation that was too much for us to overcome what we had going today.”

Or, perhaps more accurately, what Creighton (4-2) didn’t have going.

The Jays’ drop coverage, anchored by 7-foot-1 rim protector Ryan Kalkbrenner, forced the Aztecs (3-1) to take the shots they wanted, but SDSU hit them. Defender nearby? Didn’t matter. Outstretched arm? Nope. Unchallenged, uncontested looks? You bet.

But for the second consecutive game, CU’s glaring, costly problem was its offense, and missing starting point guard Steven Ashworth (ankle) didn’t help.

The Aztecs fronted Kalkbrenner and crashed down on every one of his post touches, and the Bluejays — 33.9% from the field, including 19.4% on 3s — never made them pay for a defensive plan that limited Kalkbrenner and begged shooters to hit open looks on the perimeter.

Pop Isaacs’ 18 points took 20 attempts. McAndrew scored 12 in his first collegiate start. Kalkbrenner’s 11 weren’t enough.

Everyone else was a combined 5 of 19.

“Maybe it sounds like a little bit of a broken record,” McDermott said. “But we built this team on shooting, and we’re not shooting it very well now at all.”

Creighton averaged 88 points through its first four games, albeit they were all double-digit wins over mid-majors. But the Jays were stymied in Friday’s loss to Nebraska, and they couldn’t hit anything against SDSU.

In the past two games, they’re 38-114 (33.3%) from the field and 18 of 73 (24.7%) from outside.

“I feel like we’re getting great looks off of our motion, off of our sets that we do. But, I mean, there’s really no excuse,” said McAndrew, who added 14 rebounds to his 12 points for the first double-double of his college career. “We were just missing open ones. It’s something that we’ve got to get in the gym and continue to get reps up and just make shots.”

For the second straight game, the opponent’s defensive plan started — and CU’s offense ended — with Kalkbrenner.

San Diego State, similar to Nebraska, did its best to make Kalkbrenner a nonfactor and force someone else to beat them, and early it seemed as if the Jays were going to. Their first offensive possession was a paint touch to Kalkbrenner, who kicked out to freshman Ty Davis, who drove and dished to McAndrew on the wing for the first of his four 3s.

But Kalkbrenner’s first bucket didn’t come until a minute before halftime.

Creighton completed one of few successful entry passes, and the 7-foot-1 center backed down his defender and laid one in for his first made basket in 10 days. He scored on back-to-back possessions in the second half to give the Jays life.

Then Byrd cashed that triple and McDermott called that timeout.

“Basically stole Nebraska’s game plan,” SDSU coach Brian Dutcher said. “Played them front and back as best we could, tried to get to the shooters. Without Ashworth, we were able to succeed in that. Takes a certain part of their game away not having him.

“But Greg’s a good coach and he’ll get it solved. I’m just happy he didn’t get it solved against us.”

Creighton has a little more than 24 hours until it rolls the dice against No. 20 Texas A&M, an athletic, aggressive team with a similar makeup to San Diego State.

McDermott doesn’t want anyone pointing fingers after consecutive losses for the first time since the middle of last season. Unselfishness is what his program was built on, he said, and he doesn’t want that to change in the face of adversity.

What McAndrew wants is simpler than that.

After Ashworth (ankle) was carried off late in Friday’s loss to Nebraska, coach Greg McDermott said that night he thought the Bluejays’ starting point guard could be out for “a while.”

Ahead of Tuesday’s game, Ashworth got up shots and went through a series of exercises — skips, leaps, shuffles — before missing his first game since joining CU last season. It was an encouraging sign Ashworth’s injury wasn’t as serious as McDermott initially feared.

Following the loss, McDermott said Ashworth’s injury was better than he thought, especially based on what he saw over the weekend.

“He’s doing everything right to try to get himself back,” McDermott said of Ashworth. “But as I told him last night, he’s got to listen to his body on this one. We’re not going to push this thing. We’ve got to make sure we make a long-term decision that’s in his best interest.”

McAndrew, who stepped on campus this summer as the highest-rated recruit in program history, impressed in the first start of his college career. He’s seemingly taken the reins of a logjam in the frontcourt.

His 12 points and 14 rebounds made him the first Bluejay with a double-double in his first start since Baylor Scheierman two years ago, and he’s the first freshman to do that with points and rebounds since at least 1996-97.

“It was definitely exciting,” McAndrew said. “Just going out there and playing the same I have been, trying to work as hard as I can to do the right things, making sure I’m locked in defensively, offensively.

“It was no different, honestly. … I know what I’ve got to do out there.