With a teammate to his left and three Purdue defenders in hot pursuit, Kansas guard Elijah Johnson had a decision to make and roughly one second to make it. With less than 30 seconds remaining and the Jayhawks trailing by one with a spot in the Sweet 16 on the line, Johnson had just stolen the ball and ignited a fast break. Pass or drive? It was not the first time he’d faced that question.

“Earlier in the game I had dished the ball to the wing, and we came up short,” Johnson said. “So that was one of the plays where I felt like I had to just attack the rim and stop being so passive. It ended up working out for me. . . . It gave me a little confidence.”

As second-seeded Kansas enters its Midwest Region semifinal matchup Friday against 11th-seeded North Carolina State, it gives the Jayhawks confidence that Johnson has begun to opt for the aggressive route more frequently. The latest evidence: He attempted a team-high 14 shots and tallied a team-high 18 points during Kansas’s 63-60 win Sunday over Purdue. His late transition layup proved to be the game-winning bucket.

Johnson, the only regular Kansas starter this season who did not earn Big 12 player of the week honors at least once, has emerged as the Jayhawks’ driving force during the postseason. The junior entered March as Kansas’s fifth-leading scorer (7.9 points per game), shooting 29.3 percent from three-point range in conference play.

In five games this month, Johnson has averaged 16.6 points per game and has shot 51.7 percent (15 of 29) from three-point range. That production has been critical for the Jayhawks, who of late have not gotten typical contributions from forward Thomas Robinson, the Big 12 player of the year, and guard Tyshawn Taylor, who averaged a team-high 18.6 points per game in conference play.

“Without Tyshawn, we wouldn’t be this far; that’s obvious,” Robinson said. “But without Elijah, this [NCAA] tournament wouldn’t be going the way it’s going for us right now.”

With Taylor largely out of commission because of leg cramps in Kansas’s NCAA tournament opener against Detroit, Johnson shot 6 of 8 from the field and scored 15 points. Perhaps equally important, he provided the Jayhawks a steadying hand on a night in which they were not operating at full strength.

“He’s played better than his numbers; he just hasn’t shot the ball consistently,” Kansas Coach Bill Self said. “I mean, he was under 30 percent for the season from three just until two or three weeks ago, and now he’s got a little rhythm. But his confidence level just seems higher. I don’t know if there’s anything specifically that’s happened, other than the fact that maybe he’s realizing that he’s really talented. I mean, he’s a good guard.”

Guard Conner Teahan said at times this season Johnson “defaulted” to Taylor in part because Taylor was playing well and in part because Taylor is more naturally aggressive. But, Teahan said, teammates and coaches have spoken to Johnson about being less passive, and they’re finally starting to see the dividends of those discussions.

Against Purdue on Sunday, Robinson and Taylor shot a combined 26.1 percent (6 for 23) from the field, and Teahan, one of the team’s top three-point shooters, made 2 of 7 shots from beyond the arc.

“I have to thank [Johnson] because of the way I shot the ball in the second half,” Teahan said. “If that was going to be my last game, I was going to be regretting that for the rest of my life.”

It was Johnson’s three-pointer with 3 minutes 4 seconds remaining in regulation that gave Kansas its first lead of the night. It was his defensive rebound and ensuing alley-oop pass to Taylor that cut the Jayhawks’ deficit to one with 62 seconds to play.

And it was Johnson’s steal and transition layup with 23.2 seconds left that put Kansas ahead to stay.

“In the last three minutes, Elijah kind of controlled that game,” Taylor said. “He was kind of everywhere and involved in every play.”