The Wayland High junior and Division 3 North individual champ overcame a rough start by birdieing six of the final 14 holes to shoot a 3-under 67 (34-33), and capture the Division 3 Individual State Championship, at Wyantenuck Country Club. His score bested Pembroke’s Brandon Sturtevant (34-35) by two strokes, and also helped give the Warriors a sizeable edge in the team title. Wayland’s total of 298 beat Holliston by six strokes to make it a sweep, and the Warriors’ first team state title.

“I’m happier for the team, honestly,’’ Cooper said, beaming on the front steps of the clubhouse, as his teammates anxiously waited for their win to be declared official.

Wayland got in a quick practice round Sunday. Cooper, however, was not present; he was in Plymouth participating in the Challenge Cup Junior Invitational at Pinehills Golf Course. Walking blind onto a course such as Wyanetuck was no small task, considering the tricky par 3s.

“I’ve thought all along he’s one of the best players in the state,’’ said Wayland coach Steve Garvey. “When someone can come in and shoot a 67 having never seen the course, that’s pretty special.’’

Garvey caught up with Cooper after the second hole, but with no tips or pep talks. In turn, Cooper birdied the 5th, 6th, 8th, 10th, 14th, and 16th holes, using a strong drive (averaging 305 feet off the tee) and a few putts that he laughingly acknowledged, “I got lucky.’’

“I let Joe go,’’ said Garvey. “Joe’s the type of player that a slow start means a strong finish.’’

Apponequet’s Connor Peal (35-36 -71) was third, while Holliston’s Jason Lussier took fourth with a 72 (36-36).

Bishop Stang’s Connor Murphy, Hopkinton’s Jace McCarron and Wayland’s Sam Karp tied for fifth with 73s, while Danvers’s Patrick Saunders and Medfield’s Chris Melvin tied for eighth with 74s.

Cooper’s and Karp’s scores, combined with Joey Filipe (77) and Scott Smith (81) gave Wayland the decisive cushion in the team standings, and helped the Warriors get over one important hump: their archrivals.

Two-time defending state champ Weston had beaten Wayland three times this fall, twice in Dual County League play, and again by one stroke in the Division 3 North final. The Wildcats finished fourth with 310, led by Will Caro’s 78.

Bishop Stang took third with 308, while Old Rochester took fifth with 314. Danvers (315) finished sixth, and Pembroke (319) seventh. Hopkinton and Hopedale (320) tied for eighth, with Medfield (321) finishing the top 10.