MARIETTA — Walton wasn’t about to let the lead slip through its fingers again.

The Raiders completed Monday’s opening nine holes of the Cobb County Championship clinging to a two shot lead over Lassiter.

But unlike last season, when Hillgrove rallied to defeat the Raiders, Walton not only maintained its advantage, but widened it, shooting a tournament-record 290 to claim its first county championship over 13 other teams Tuesday at City Club Marietta.

All of Walton’s golfers shot in the 70s over the par-71, 5,721-yard course, helping the Raiders to an 11-shot gap over runner-up Lassiter.

Mount Paran Christian (304) was third, followed by Harrison (305), Kell (306) and Whitefield Academy (307). Kennesaw Mountain (309), Hillgrove (322), Walton ‘B’ (322), Allatoona (326), Pope (330), Wheeler (361), Sprayberry (379) and North Cobb (386) rounded out the field. South Cobb did not have enough golfers to earn a team score.

“It feels pretty good to win this,” Walton coach Mike Davidson said. “We finally finished what we started. We had a chance last year, but Hillgrove slipped in and knocked us out of it. But we finished (Tuesday). These guys practice hard at Indian Hills, and I think working hard there really prepared them for this.”

Defending individual medalist John Yi shot Walton’s low round. The sophomore posted a 1-under 70 to tie Whitefield’s Anders Olsson after 18 holes.

Yi and Olsson went into a playoff, and each parred Nos. 1 and No. 9 before darkness suspended play. The two were declared co-champions.

Yi pushed his tee shot right on the first playoff hole, but Olsson also missed right. Both were short of the green with their approach shots, and their pitches onto the green rolled to within 2 feet of the cup before both settled for par.

The second playoff hole was routine, with both Yi and Olsson hitting the fairway. Olsson’s approach landed on the green 10 feet below the hole, while Yi was left with a long birdie putt from above the flag.

Both golfers parred the hole before play was suspended.

“It feels good to defend the championship,” Yi said. “Anders is pretty tough. I thought I didn’t have (the championship) at first, but I hung in there.”

Olsson was also pleased with the way things ended.

“It’s a great feeling to be co-champ competing in this tournament for the first time,” said Olsson, a senior who will play collegiately at Georgia Southwestern State University this fall. “When I heard I’d be competing against John, my heart raced because I’ve played against him before and he’s a great player.”

David Yowell and Connor Edison each shot 73 for Walton, while Matt Flynn and Tanner Landry both had 74s. Michael Sheahan carded a 76.

Lassiter, which won the inaugural county title in 2010, was led by Adam Wright (74), Brody Judd (74), Max Weyrick (74) and Parker Usry (79).

“We didn’t shoot a bad score, but Walton shot lights-out,” Lassiter coach Butch Burden said. “They played well.”

Individually, Whitefield’s Ty Hampel finished third with a 71, while Kennesaw Mountain’s Jonathan Keppler and Mount Paran’s Tyler Young each shot 72 to tie for fourth. Kennesaw Mountain’s Cole Hunsucker, Kell’s Matthew and Michael Hines, Hillgrove’s Kurt Brucker and Mount Paran’s Preston Moore shot 73, while six others shot 74.

Young shot a 1-under 35 on Monday’s front nine to tie for the lowest round, but three bogeys dropped him to a 37 on the back nine. Yi and Olsson both shot even-par 36 Monday and carded 1-under 34s on the back nine.

Yi birdied holes 11 and 12 to go with a bogey on 15. Olsson birdied 13 and birdied the par-4 18th to force the playoff.