BLOOMINGTON -- A double-digit lead quickly evaporated into a four-point advantage as the fourth-quarter clock reached its halfway point, putting the Rock Island boys' basketball team in a spot that would challenge their character.

Ninety seconds later, the Rocks had their response.

Needing to answer a Normal Community rally on Thursday night, Rocky displayed its tenacity when Trey Sigel's 3-pointer capped a possession that took 90 seconds off the clock. The shot gave the Rocks the jolt they needed to grab a 62-50 win in the State Farm Holiday Classic quarterfinals at the Shirk Center.

"It's all heart," Rocky junior guard C.J. Carr said. "The games we've lost, we had leads and let them go. We didn't want to do that again. We wanted to get that 'W.'"

Before that possession, the Rocks (10-2) lost their grip on the game. Normal (4-6) opened the fourth quarter on a 6-0 run that cut a 10-point Rocky advantage down to 49-45 with 6:15 left in the game.

After Callen Boodie's layup capped the 6-0 run, Rocky took its ensuing possession and patiently waited for the right shot. Ninety seconds passed before Sigel caught the ball at the top of the key and immediately buried a 3-pointer.

Before that, the junior guard was 0-for-5 from long distance.

"That was huge," Carr said. "A great shot."

Now holding a 52-45 lead after the big triple with four minutes left, the Rocks closed the game with a flurry. Rocky made 11 of the final 17 shots to reach the tournament semifinal for the second time in three years.

Rocky meets Chicago North Lawndale in tonight's 6 p.m. semifinal at the Shirk Center.

"To make plays, that's big," Rocky coach Thom Sigel said. "We hope that's progress."

When it counted, the Rocks were at their best. They made their final three shot attempts and went 7 of 8 from the foul line in the last four minutes.

"We finished the game," Thom Sigel said. "We did a great job, rotated well, got turnovers, got the ball where we needed and made shots."

For the most part, Rocky played a complete game. The Rocks shot 52.3 percent (23 of 44) from the field and committed a season-low six turnovers. Carr scored a game-high 20 points with three assists and two steals, Raahsaan Brown had nine points and Rob Johnson grabbed seven rebounds.

Still, the solid performance had some head-scratching stretches, with the start of the fourth quarter a perfect example. On their first four possessions, the Rocks missed three shots and committed a turnover. The Ironmen turned those into six points.

One possession changed the complexion of the game.

"I debated calling a set," Thom Sigel said. "But with our quickness and having the (49-45) lead, we were going to run our offense. We wanted to make sure we weren't going crazy. We held it longer than we thought, but credit the kids for some composure."

The 90-second stretch helped give Rocky a double-digit win and third consecutive victory.

"Any win is a confidence builder," Carr said. "We want to keep building on it."