A fifth set seemed inevitable, and that’s a place where the Cougars have struggled this season.

Instead, the BYU outscored the home team 12-5 the rest of Set 4, getting a huge block from Brielle Kemavor at match point for the 3-1 (25-21, 25-19, 19-25, 25-23) upset victory on Saturday at Schollmaier Arena.

The Cougars (17-4, 5-4 Big 12) snapped the Horned Frogs’ 18-match home win streak, led by Suli Davis’ 20-kill, 10-dig double double, her fourth of the year.

Davis was joined in double figures by Sophia Callahan, who had a career-high 15 kills on a .365 clip, and Brielle Kemavor’s 11, hitting .348. It is just the fourth time this season that BYU has had three hitters with double-digit kills.

Alex Bower dished out 46 assists and was a dig shy of a double-double of her own. Lulu Ululave added 10 digs as well, with Claire Little Chambers contributing eight.

Kemavor finished with a match-high eight blocks while Bower posted three. Callahan, Little Chambers and Elli Mortensen each had two.

Leading two sets to one, BYU and TCU went back and fourth in Set 4 with eight ties and two lead changes before the media timeout, with Callahan’s six kills in the set pacing BYU in the early going. Davis and Kemavor kills sandwiched a double block by the duo, and two more Davis kills had BYU within two, at 20-18. Consecutive Mortensen kills then forced a TCU timeout down by one, 21-20.

Three straight from the Cougars, including two double blocks involving Kemavor, flipped the script and forced the Frogs’ second timeout. A Callahan kill got BYU match point, and a Kemavor big block finished things off a play later for the 25-23 win.

The Cougars led Set 1 11-7 after a pair of 3-0 runs that both featured double blocks, a Davis kill and Horned Frog error. Abby Hoybjerg, Little Chambers and Kemavor each landed kills with the Cougar advantage at 15-10. Kemavor scored two more times before kills by Davis and Hoybjerg as well as another TCU error put BYU in front, 20-16, forcing the Frogs’ second timeout. TCU took four of the next five points, however, and the Cougars called timeout.

After a Horned Frog ace cut the lead to 22-21, BYU closed the set on a 3-0 run with a Little Chambers kill and block before a Kemavor overpass kill for a 25-21 win. The Cougars hit .407 in the opener, holding TCU to a .194 clip.

Trading points early in Set 2, a 4-0 run capped off by consecutive Little Chambers aces gave BYU a 7-5 lead. Another 4-0 span by the Cougars, featuring kills by Callahan and Davis, forced a TCU timeout ahead 13-10. BYU maintained its four-point advantage through 17-13. Responding to a 3-0 Horned Frog run with three of its own, back-to-back Davis kills before a back row Little Chambers hammer forced another Frog timeout leading 20-16.

Another pair of Davis kills, along with a Callahan shot down the line gave the Cougars set point, and after trading service errors, they would take a commanding 2-0 lead in the match, 25-19.

TCU rebounded to win Set 3 to force the fourth set but couldn’t push the match to a fifth.

The Cougars will return home for a pair of matches against UCF and Kansas State on Wednesday and Friday next week.