AMES — Iowa State crafted the run.

Texas drilled the shot.

Both events led to overtime Wednesday — and the expected Big 12 season-opening stress for Cyclones coach Bill Fennelly.

“We’ve only got 17 more of these to go,” said Fennelly, whose team survived the Longhorns’ upset bid 73-65 before a crowd of 7,121 at Hilton Coliseum. “I told our team before the game, I told them at halftime, I told them after the game: ‘Welcome to the Big 12.’”

And this time, ISU ushered in the conference season with a win.

The Cyclones (10-1, 1-0) started 0-5 in Big 12 play in 2011-12 before rallying for nine wins in 12 games to reach their sixth straight NCAA Tournament.

“It motivates us,” said ISU forward Chelsea Poppens, who scored 16 points while battling foul trouble. “It shows us what we’re capable of and that we won’t back down.”

ISU reeled off 10 straight points in the last 3:52 of regulation, with Poppens punctuating the run by grabbing an offensive rebound off a missed free throw and sinking two from the line to put her team ahead 57-53.

Just 32 seconds remained, but the Longhorns’ Ashley Roberts drained three free throws, the Cyclones’ Brynn Williamson countered with two, and the ball found its way to Texas star Chassidy Fussell’s hands with five seconds left.

She swished a 3-pointer, forcing the extra session.

“A big-time shot from a great player,” Fennelly said.

In overtime, ISU point guard Nikki Moody made her team’s only two field goals, but free throws from Hallie Christofferson, Williamson and Poppens cemented the win over the Longhorns (7-5, 0-1).

Anna Prins led the Cyclones with 17 points before fouling out.

Moody had 14 points and 10 assists.

Fussell scored 15 points — two below her season average — for Texas, which was outscored 27-10 at the foul line.

Four Longhorns fouled out and star post player Cokie Reed played more than 10 minutes with four fouls.

“I think it was the effect of us trying to keep them off the 3-point line and just not being smart enough,” Texas coach Karen Aston said of her team’s 30 fouls to ISU’s 16. “Big 12 officiating is good. … That’s on us.”

Williamson, who played all 45 minutes, guarded Fussell most of the night, but extended help arrived as needed.

“Brynn stepped up big time,” Moody said. “She did exactly what we needed her to do.”

That’s a lot.

“I said in the shoot-around today, ‘If Chassidy (Fussell) runs to the restroom, run with her,’” Fennelly said. “That was her job and I thought she did a great job of it.”