Rancho Bernardo girls basketball coach Kai Harris recently told sophomore guard Kaylee Presnell that “her best game was getting ready to happen.”

Presnell picked the perfect time to make her coach’s prediction come true. She scored a career-high 22 points — including five 3-pointers — sparking the Broncos to a 53-44 victory over Kearny to win the San Diego Section Division III championship Friday afternoon at Jenny Craig Pavilion.

“It’s been a long time coming,” said Harris. “It came at the perfect time for us. I had a feeling. I knew when those first few dropped it was going to be a great night for her.”

Presnell had just 15 3-pointers all season, so she wasn’t expecting to light it up from outside.

“Not at all,” she said after RB claimed its first title in 17 years. “Honestly, I thought I’d have five or six points.”

Presnell had nine points by halftime, helping RB to a 21-18 lead. She added a pair of 3-pointers midway through the third quarter when the Broncos went on a 13-3 run that provided a 34-21 lead.

But Kearny came back with a run of its own, the Komets’ defense fueling an offensive spurt that got them back in the game.

“I call it poised pressure,” said Harris. “They weren’t necessarily attacking the ball, but just the little halfcourt trap they were doing was enough to throw us off rhythm.”

The Komets (22-6) took a 44-42 lead on Aitana Garland’s 3-pointer midway through the fourth quarter.

But Harris had prepared the Broncos for this moment.

“We often talk about how preparation breeds champions,” said Harris, who used a 6-on-5 drill in practice the day before the final. “For them to mentally see the picture in practice and instantly see it the next day really helped.”

It also helped that right after Garland’s basket, Presnell responded with her fifth 3-pointer to give RB a 45-44 lead and restore order.

“That was intense,” said Presnell, “but I’m really glad it happened.”

Harris called Presnell shot “the dagger in the heart.”

Kearny did not score over the game’s final five minutes.

RB’s Aly Murray added 12 points for the Broncos. Jennell Garland led Kearny with 12 points and Aitana Garland had 11.

Both teams are expected to advance to the state playoffs.