West Aurora played with poise under pressure for a half.

Playing with a purpose, Josh McAuley did all night.

It all unraveled in five fateful minutes.

Proviso East wiped away West Aurora’s workmanlike 1-point halftime lead with a back-breaking 17-0 third-quarter run, beating the Blackhawks for the second straight year 62-52 at Tuesday’s Class 4A Hinsdale Central supersectional.

Asked how it all went awry, West Aurora coach Gordie Kerkman had a simple answer.

“Speed kills, even in basketball,” Kerkman said. “They (Proviso East) turned it up a notch in the second half.”

Kerkman’s charges had the game to their liking for a grind-it-out half.

West Aurora (24-7) led 16-11 after a first quarter featuring 6 lead changes, much on the strength of Spencer Thomas’ early 9 points. Proviso East (29-3) never strung together more than two straight baskets in the first half, and West Aurora outrebounded the Pirates 18-9.

A deep 3 by Jevon Carter took the Pirates into the break down 24-23, and coach Donnie Boyce was waiting for them in the locker room with a stern message.

“I told them if you all want to continue to play, you better match (West Aurora’s) intensity,” Boyce said. “I thought in the first half they withstood our pressure real well, but basketball’s a game of runs. The way the game was going in the first half, the tempo of the game, that wasn’t our game.”

Proviso East went ahead on Sterling Brown’s three-point play, but McAuley momentarily gave West Aurora back the lead at 29-28, rolling in a short runner.

It went downhill from there.

Brown buried a jumper, and Reginald Osborne took in a steal for a score. After another Blackhawks turnover, Paris Lee hit a 3 and Osborne scored again off a turnover.

A McAuley dunk to close the quarter made it 45-31, but when the dust cleared the damage was done. West Aurora turned it over 9 times in the quarter, after coughing it up only 8 times the entire first half.

“We were starting to get out of our gameplan late in the first half and it just carried over into the second half,” Kerkman said. “We really didn’t run much offense at all in the second half and I think you have to give Proviso East part of the credit for that. Their quickness forced us into a lot of turnovers.”

West Aurora isn’t used to bearing the brunt of other team’s pressure, but it’s business as usual for Lee and a collection of quick Pirates guards.

“We practice defense for an hour every day,” Lee said. “I feel they got a little winded.”

Lee was a big reason behind a difficult night for West Aurora’s Jontrell Walker. The Blackhawks’ junior point guard, averaging a team-best 17.8 points per game, missed his first 5 shots, turned it over several times under pressure and went scoreless until hitting a 3 with 6:37 left in the game.

“Paris Lee, he’s the best on-ball defender in the state,” Boyce said “He’s the best point guard in the state in my opinion.”

“We let their pressure get to us,” said Walker, who finished with 6 points. “We were ready for it. They started to play fast and we tried to play fast with them.”

The Pirates had no answer for McAuley, though. On the court against a pair of future Division I players in SMU recruit Brown and Illinois State-bound Lee, McAuley was sensational with 22 points, 18 rebounds and 4 blocks.

The 6-foot-7 senior even hit a pair of 3s in the fourth quarter, the second pulling the Blackhawks within 56-49 with 2:01 left.

“He had a heck of a game, and Josh is capable of that,” Kerkman said. “And that was against good competition.”

Brown had 10 of his 14 points in the second half and Lee scored 18 points for Proviso East, which advances to face three-time defending 4A champion Simeon in a 6:30 p.m. semifinal at Redbird Arena in a rematch of last year’s 4A final. The Pirates, unbeaten since a December loss to Morgan Park but perhaps flying under the radar, can’t wait.

“I’ve had that taste in my mouth for a year. I’m sick of it,” Lee said. “And now I have a chance to get rid of it.”

Follow Josh on Twitter@jwelge96