That got the Cougars' attention.
Jonathan Tavernari ended up scoring 23 points, Jackson Emery and Charles Abouo added 22 each, and BYU went on to a 107-77 rout of TCU on Saturday. The win allowed BYU (28-4) to match the 1950-51 team for the most in school history.
Jimmer Fredette finished with 18 points for the Cougars (13-3 Mountain West), who beat the Horned Frogs for the 12th straight time. Ronnie Moss had 17 points to pace TCU (13-18, 5-11).
"He asked us what we thought was going to happen, [if TCU] was just going to roll over and let us do whatever we wanted," Emery said. "He brought us back to reality, that we weren't going to be given the game, that we had to earn it."
TCU bolted to an 18-4 lead, hitting its first seven field goal attempts, including 3-pointers from Keion Mitchem, Zvonko Buljan and Edvinas Ruzgas.
During a timeout after the TCU run, BYU's starters heard plenty from Rose about the slow start. The subs picked up the pace defensively, answering with a 27-11 spurt to move in front 31-29 with 8:07 left until halftime.
The Cougars ran off 11 unanswered points late in the first half, including 3s from Tavernari, Fredette and Emery, and led 57-43 at the break.
"[TCU] came out with a lot of energy and a great game plan," Rose said. "We had problems getting the ball stopped in transition to start the game. They got great looks and that turned them on. But I was pleased with how our guys responded to what TCU was doing."
Emery said shutting down the easy baskets TCU was getting early keyed the turnaround.
"They had layup after layup, wide-open shots -- it was like a walk-through for them," Emery said. "Give them layups, they're going to make them, which is what we did the first couple minutes."
The teams will meet for the third time this season in the conference tournament, which starts Wednesday in Las Vegas. Second-seeded BYU faces the No. 7-seed Horned Frogs on Thursday.
BYU has beaten TCU twice this season by a combined 50 points, but Rose said overconfidence won't be a problem on Thursday.
"It'll be a real challenge," Rose said. "The first 10 minutes of the game will be a real emphasis for us after how they came out against us today."
Tavernari had 16 first-half points, going 4 for 6 on 3-pointers, to spark the turnaround. The Cougars shot 62 percent for the game, including 56.5 percent from 3-point range.
Backed by a cheering section that made more noise than TCU fans, Brigham Young led by as many as 32 in the second half. Abouo, who established a career-high for points, hit a 3-pointer with 4:27 left to stretch the Cougars' advantage to 101-71, and Rose cleared his bench.
TCU coach Jim Christian said his team stopped sharing the ball after the fast start. The Horned Frogs were also undone by 24 turnovers.
"We had six assists in the first five minutes, and six assists for the half," Christian said. "We became a little too much one-on-one, guys trying to make plays that weren't there. When you turn the ball over against BYU, who likes to get up and down, you're in trouble."
The Cougars scored 100 or more points for the third time this season. They had 110 in a win over Nevada on Dec. 23 and 107 while beating Southern on Nov. 24.