Growth isn’t linear and after Duke proved in the first game of its western road trip how much it’d grown from its first big game to its second one, the Blue Devils’ third big game was a reminder of how much further they need to go.

Duke lost 75-72 to Kansas on Tuesday night at T-Mobile Arena in Las Vegas.

That was in spite of Kansas’ star being ejected from the game about midway through the second half; in spite of Duke (4-2) making 11 3-pointers; and in spite of Duke shooting 50% and assisting on 17 of 24 field goals (70.8%).

The part that killed the 11th-ranked Blue Devils was, similar to the loss against Kentucky, late turnovers by freshmen.

In the final minute with Duke trailing by one, Cooper Flagg turned the ball over while trying to spin through the middle of the lane — not a carbon copy, but similar to two weeks ago in Atlanta.

Duke got a defensive stop and took another run at it; this time, Kon Knueppel got trapped in the air with two Kansas defenders coming at him. He threw a wayward pass that was picked off with about 3 seconds left.

The Blue Devils got one more shot, after a couple of free throws by Rylan Griffen (Kansas was 11-for-12 at the free-throw line; Duke was 13-for-18).

Knueppel got a contested shot from about 35 feet off; it hit the square and rattled around the rim briefly before clanging out.

It’s Duke’s second loss out of three big non-conference challenges so far, coming against the No. 1-ranked team in the AP Top 25. Kansas (6-0) now has wins over North Carolina, Michigan State and Duke.

The Blue Devils have one more non-conference game that looms large — after playing host to Seattle on Friday night, Duke plays Auburn in the ACC-SEC Challenge next Wednesday night in Durham.

They’ll go into that one knowing they missed a decent shot at a 2-0 western road trip.

With about 10½ minutes left, Kansas star center Hunter Dickinson was ejected from the game for a flagrant-2 foul. After missing a shot, Dickinson was undercut by Maliq Brown on a box-out; after they both tumbled to the ground, Dickinson swung his right leg into Brown’s head.

After a long discussion between officials, the fifth-year center with a bit of a reputation for such antics was ejected.

Following Dickinson’s ejection, Duke was whistled for seven fouls and Kansas was called for two.

Duke only led this game three times — one in the opening minute, another in the opening minute of the second half, and lastly at 67-65 with 5:53 left. That was on a dunk by Flagg, who scored 11 of his 13 points in the second half, and it was answered by a 3-pointer from Griffen on Kansas’ next possession.

Turnovers were as much a problem for Duke as they were for the Jayhawks, both teams committing 16 of them. The difference was in capitalizing on them — Kansas held a 21-15 advantage in scoring off turnovers.

Tyrese Proctor led Duke with 15 points, all of them coming on a 5-for-7 clip on 3-pointers. Along with Flagg’s 13 points, Knueppel scored 11 and dished out eight assists — though he was 0-for-8 from 3-point territory. Sion James scored 10 points off the bench.

Kansas fired the first punch and kept it going until its lead was 16-3 after a little more than four minutes. It wasn’t until the Jayhawks were up 23-10 that Duke started clawing its way back into the game.

After AJ Storr missed the first shot of the game, Dickinson made a put-back. That kicked off a string of seven straight makes for Kansas — three of them being 3s.

Things steadied for Duke after the initial blasts. The Blue Devils started the game shooting 4-for-12 and ended the first half making nine of their last 14 shots.

Duke had a 12-0 run to tie the game at 32-32 late in the first half. During that stretch, Brown hit his first 3-pointer of the season — meaning all eight players in Duke’s main rotation have made at least one 3.

The Jayhawks pushed back from there and took a 41-39 lead into halftime — and it was only that close because Proctor stroked a 3-pointer as time expired in the first half.

TIP-INS: Knueppel is 1-for-16 on 3-pointers in Duke’s two losses; he’s 12-for-24 in the four wins. … Brown scored eight points; he scored a combined 10 in Duke’s first five games. … Kansas was led by Dajuan Harris Jr.’s 14 points and nine assists, with the senior point guard only committing two turnovers. … The Jayhawks outrebounded Duke 31-25, marking the first time Duke has lost the rebounding battle this season.