ORANGE COUNTY CHAMPIONSHIPS:

MISSION VIEJO — Shelby Buckley enjoyed a return to Orange County on Saturday, even if her competition in the girls’ 800-meter run couldn’t say the same.

The Corona del Mar High senior won the race in 2 minutes, 16.37 seconds, highlighting Newport-Mesa finishers in the Orange County Championships at Mission Viejo High.

CdM junior Blaine Bolus was the other local winner, breaking his own week-old school record in the triple jump with a mark of 46 feet, 7 1/4 inches.

Both Sea Kings also finished second in an event. The UCLA-bound Buckley’s time of 4:52.28 in the 1,600 was bettered only by Woodbridge’s Christine Babcock.

Bolus, who jumped 21-11 in the long jump, was just edged by Trabuco Hills’ Trevor Wightman by half an inch.

For Buckley, it was a welcome result after she was disappointed by her sixth-place finish in the 1,600 last weekend at the Arcadia Invitational. She also hadn’t run the 800 at an invitational since her time of 2:14.02 at the Irvine Invitational on March 8 broke that meet’s record.

On Saturday, she was second halfway through the race, but had an impressive kick on the second and final lap.

“Coach told me to decide a plan after 150 [meters], so I did,” said Buckley, who has the third-fastest girls’ 800 time in Orange County Championships history, set last year. “I just wanted to stay second or third, then I was going to kick the last 200, 300 meters. My time wasn’t that impressive, but I stuck to the plan, so I’m happy. And, I got first, so I’m happy as well.”

Buckley also ran the anchor leg of the meet-ending 4x400 relay. She, along with freshman Sarah Craig and juniors Tina Theriot and Claire Schmidt, placed third in a season-best 3:59.36.

“At the end of the day, to run a PR when your kids are pretty zapped, that was good for us,” CdM Coach Bill Sumner said.

Bolus, a junior who owns the CdM records in both the triple and long jump, said he nearly won both events Saturday, but was happy with his distances.

“I thought I had [the long jump] won, but [Wightman] came in from a different event and ended up having a big PR and beating me by half an inch,” he said.

CdM junior Kim Condino was fourth in the girls’ 800, in 2:19.37, while Craig ran a personal-best 59.37 seconds to place sixth in the 400. She said she’s hoping to run under 59 by year’s end.

“I’m pretty happy,” Craig said. “I’m a freshman, so it’s all kind of new to me. It has such an energy because there’s so many people here. It’s really fun. I totally look forward to hopefully doing it three more times.”

Newport Harbor senior Sophia Ditty was sixth in the girls’ 3,200 in 11:06.59, while junior teammate Desiree Alexander was 10th (11:14.88) and CdM senior Allison Damon was 11th (11:15.90).

“I wanted to break 11 [minutes],” Ditty said. “Next time, I’ll get it.”

Sailors senior Rex Nelson said he was originally supposed to race in the 800, but he swapped with junior teammate Michael Taylor. Nelson went on to finish sixth in the boys’ 1,600, in a personal-best 4:20.30. The time beat Nelson’s old PR by about six seconds, Coach Nowell Kay said.

“That was a nice breakthrough for him,” Kay said.

Also in the boys’ 1,600, CdM senior Thomas Dialynas was ninth in 4:21.23, and Dialynas also finished eighth in the 3,200 in 9:35.14. Both times are personal-bests.

Costa Mesa also had some solid performances, including a sixth-place finish by sophomore Tatiana Williams in the girls’ triple jump (33-9 1/2 ), and the Mustangs’ Rachel Daley jumped 5-0 in the high jump to finish tied for sixth.

Estancia junior Fernando Orozco was ninth in the boys’ 1,600 rated race, in 4:33.33, while Newport Harbor senior Avery Paulson cleared 12-9 for ninth place in the pole vault.

For the Sailors’ girls, Cassidy Gayner was 10th in the 300 hurdles in 46.86 seconds.

Sage Hill junior Cait Williamson finished 16th in the girls’ 1,600, but her time of 5:10.88 broke her own school record by about six seconds, Coach Nate Miller said.

“I’ve been wanting to PR by that much all season,” said Williamson, who also finished 13th in the 800. “It was nice to be in such a big race, to have people pull me along. I was thinking more about my position in the race than concentrating on the splits. It was a different way for me to run, but it worked out really well.”

Dana Hills won both the boys’ and girls’ varsity team titles. CdM, which had won its first girls’ team title last year, was fifth on Saturday.

MATT SZABO may be reached at (714) 966-4614 or by e-mail at matthew.szabo@latimes.com.