KANSAS CITY, Mo. -- Iowa State kept giving away the ball, and Texas Tech kept making the Cyclones pay.
Jarrius Jackson converted three last-minute turnovers into six free throws Friday, sealing the Red Raiders' 64-56 victory in the second round of the Big 12 Tournament.
"We turned the ball over 17 times, and they weren't even pressing us," Iowa State coach Wayne Morgan said. "They had 17 points off our turnovers. That is the key stat."
Jackson led the fourth-seeded Red Raiders (19-9) -- who advanced to the semifinals for the fourth straight year -- with 20 points. Texas Tech will meet top-seeded Oklahoma on Saturday.
Fifth-seeded Iowa State (18-11) scored just six points after the midpoint of the second half and lost despite a 42-32 rebounding advantage.
"There were three or four times that we had clean shots, good looks that just didn't go in," Morgan said.
Texas Tech trailed by eight with just under 9½ minutes remaining, but then went on a 14-2 run -- capped by Curtis Marshall's dunk with 1:41 left -- for a 56-52 lead.
Curtis Stinson flipped in a layup with 1:29 left, getting the Cyclones within 56-54, but Devonne Giles rebounded Ronald Ross' miss at the other end and hit two free throws with 52.4 seconds left to make it 58-54.
Iowa State turned the ball over on its next three possessions, and Jackson capitalized with a 6-for-6 line performance that iced the win for the Red Raiders.
Giles had nine points and nine rebounds and Ross had eight points in the first half for Texas Tech, which led 34-32 at the break. But for much of the second half, Iowa State's zone defense kept both largely in check.
Giles didn't pick up his first rebound in the second half until 6:13 remained, and didn't score until his basket with 4:40 left cut Iowa State's lead to 50-49.
"It's hard to get the ball in the middle sometimes because it's so packed up," said Giles, who finished with 13 points and 12 rebounds. "But the guards did a good job of driving over the top and getting it to the post."
Ross' first basket of the second half came even later, at the 3:19 mark -- but it was a big one, part of a 3-point play that tied the game at 52.
Ross had 11 points for Texas Tech, and Martin Zeno and Marshall added 10 each.
Stinson led Iowa State with 24 points. Jared Homan fouled out with 14 points and 12 rebounds, and Will Blalock added 12 points.
Both teams hit shooting slumps midway through the second half. The difference was that Texas Tech recovered.
"We came back today as well as we ever have," Red Raiders coach Bob Knight said. "The coming back was a real highlight of the team's competitiveness."
The Red Raiders came within 42-40 on Jackson's basket with just under 12½ minutes remaining, then went scoreless from the field until Jackson hit a 3-pointer with just under six minutes to go.
Iowa State built its lead to 50-42 on Stinson's driving layup with 9:25 to go -- then didn't score again until Stinson hit a jumper with 3:34 left for a 52-49 lead.
While Stinson had 16 points in the second half for Iowa State, Homan had only two points on 1-for-5 shooting after the break.
"I felt it was myself missing out," Homan said. "I didn't feel like I had a good game. I missed a lot of easy shots. I take that upon myself."
It didn't help that Texas Tech threw everything it had into shutting down the Cyclones' center in the second half.
"At halftime, we knew we had to concentrate on our help defense," Jackson said. "It had to come from everyone on the team."
The Cyclones, who hit their first four 3-point tries and shot 6-for-15 from long range in Thursday's 77-57 first-round win over Baylor, were 0-for-6 from outside the arc on Friday.
Forward Rahshon Clark, who scored a career-high 20 points against the Bears, fouled out without scoring Friday.
