West Virginia’s Javon Small gestured and yelled for a teammate — any teammate — to get open closer to the basket. When that didn’t work, the Big 12's leading scorer forced up a 3-pointer just before the shot clock expired.

Clank.

Small was the latest star stifled by No. 6 Houston, which has been making a habit out of sapping opponents' strengths.

The Cougars (17-3, 9-0 Big 12) are riding a 13-game winning streak behind the nation’s stingiest defense and priding themselves in slowing down the other team's top scorers.

“We’re a defensive-minded team," Houston guard L.J. Cryer said after a 63-49 win over the Mountaineers on Wednesday night. "We go to practice and we emphasize defense a lot. You achieve what you work on and what you emphasize. When the ball’s not going in, you’ve got to rely on your defense. And on the nights that the ball isn’t going in, we’re going to win because of that.”

Opponents have to find a Plan B when Houston throws double and triple teams at them. Cryer, Joseph Tugler, J'Wan Roberts and Terrance Arceneaux took turns harassing Small, who attempted just seven shots and was held to eight points, nearly 12 below his league-leading average.

It's happened quite often this month.

UCF's Keyshawn Hall, who scored a career-high 40 points in his previous game, was held to six points against Houston on 2-for-12 shooting.

Utah's Gabe Madsen was limited to eight points on 3-of-10 shooting against the Cougars. The Utes, who have scored at least 80 points 10 times this season, were held to 36 points, their lowest scoring output since 2011.

BYU's Richie Saunders managed just nine points against Houston one game after scoring a career-high 30 against Arizona State.

Houston, whose 18-game league winning streak dating to last season is the second longest in Big 12 history, is allowing 55.6 points per game, 2.4 points fewer than the next best defensive team, Drake. Opponents are shooting a national-worst 36% from the field against the Cougars.

Houston started the season ranked at No. 4 but started 4-3 with overtime losses to San Diego State and No. 4 Alabama in Las Vegas and a five-point loss to top-ranked Auburn.

It hasn't lost since.

Kelvin Sampson, who has been Houston's coach since 2014, said defense has been the Cougars' bread and butter for nearly a decade. He's especially proud that in this era of the transfer portal and name, image and likeness opportunities, he's able to teach the same players. Eight of Houston's top 10 players returned this season, including four starters.

“And that does make a difference,” Sampson said. "Part of our secret sauce is our program. And then having great kids. Character matters. Having kids you don’t mind losing with. There’s some teams, whether it’s bad attitudes or wrong attitudes or what, you’re always having to coach that. I never have to worry about effort or attitude. I’m blessed that way. I’ve got a great staff. That’s buoyed us here for a long time.”

Cryer is Houston's top scorer averaging 13.5 points per game — which is 18th in the Big 12 — followed closely by Emanuel Sharp at 13.4. But Houston is filling the basket enough that its average 21-point scoring margin leads the country, and the Cougars are forcing 6.1 more turnovers than they commit, good for fourth best.

“Defensively, they’re just well connected," West Virginia coach Darian DeVries said. "They’re very aggressive. They really load to the ball. It’s hard to really crack them.

“Not many teams have.”