Lawrence High sophomore Justin Roberts (5) hangs in the air as he scores against Shawnee Mission West defenders Zach Witters (14), Justin Fetzer (15) and Louis Rollins, right, during their game, Tuesday at LHS. The Lions boys won, 64-50.

Lawrence High sophomore Justin Roberts wasn’t going to watch the LHS boys basketball team lose on his watch.

After a disappointing first half that found the Lions trailing by three points, Roberts scored 11 of his game-high 19 points and grabbed three steals in the third quarter as Lawrence beat Shawnee Mission West, 64-50, on Tuesday night at LHS.

“We just knew we had our backs against the wall,” said Roberts, who also had four rebounds. “We knew the only way we could get ahead is by getting some energy and causing some turnovers.”

Lawrence (7-1, ranked No. 5 in 6A) went on a 14-0 run to close the third quarter. The Lions held SM West scoreless for nearly six minutes as they switched to a full-court defense in the second half. In that time, LHS forced six turnovers and shot 6-for-13 from the field.

“We came out and got them back on their heels,” Lions coach Mike Lewis said. “Our guys had that sense of attacking them and they went after them. Our energy from our defense created those offensive looks and our adjustment defensively is what led to that big third quarter.”

Roberts opened the second half by scoring on a mid-range jumper. On the team’s second possession, he missed another jumper, but got his own rebound and put it back up for a layup.

The Vikings (1-7) extended their lead to 37-33 after a Jesse Wilkins layup with 5:44 remaining in the third quarter. Although Roberts scored on a layup 10 seconds later, both teams went scoreless for nearly two minutes.

Coming out of a LHS timeout with 4:03 left in the quarter, junior Anthony Bonner got a steal and passed the ball ahead to a wide-open John Barbee, who converted the layup to tie the game, 37-37. SM West turned the ball over on the subsequent inbounds, which led to Roberts scoring on a layup, drawing the foul and converting the free throw to give the Lions a three-point lead.

Roberts was able to get a steal on the next defensive possession, and went coast-to-coast for a layup to put the Lions up 42-37. With the crowd roaring two possessions later, senior Anthony Riley found Bonner for a three-pointer. The Lions held the ball for the final minute of the quarter, which ended when Bonner drove in for a layup at the buzzer to give LHS a 47-37 lead.

“Coach kept us telling us in the locker room to be aggressive and be the first one to punch them back,” said Barbee, who scored 13 points and added six rebounds. “So that’s what we did in the second half.”

The Lions continued their momentum in the fourth quarter, opening with a 13-3 run. After a layup by the Vikings, senior Connor Henrichs drove from the corner for a baseline layup while also drawing the foul. A few possessions later, sophomore Price Morgan fought his way inside for a layup before blocking an SM West layup attempt a few feet out of bounds on the defensive end.

Bonner dominated in the first quarter, scoring 10 of his 17 points. He drew the foul and converted his layup on an alley-oop attempt from Roberts to give the Lions a 5-2 lead, before drilling a three-pointer on the next possession. In the last 30 seconds of the opening quarter, Bonner made back-to-back layups on the team’s last two possessions.

SM West pushed ahead in the second quarter by scoring in three of its last five possessions before the half.

“That first half, a couple of those guys (on SM West) really shot the ball well,” Lewis said. “We didn’t have them scouted to be that kind of shooters. But that’s basketball. You’re going to face teams on nights who do some things well that you’re not expecting and you have to make the adjustment defensively and be able to dig in and hang on. Our guys did a nice job of that.”

The Lions will face Olathe East (7-1, ranked No. 4 in 6A) at home on Friday.