Rancourt, a 17-year-old high school senior from South Portland who attends the David Leadbetter Golf Academy in Bradenton, Fla., captured the Southern Maine Women's Golf Association championship Tuesday in her first SMWGA event.
She finished with a two-day total of 149, 1-over-par for the 5,575-yard setup for women at the Brunswick Golf Club.
Rancourt finished nine strokes ahead of Kate Merrill, the 17- year-old reigning Maine schoolgirl champion from North Yarmouth Academy, in the tournament's first flight.
"It was great to watch them play. They were steady," said Barbara Rondeau of Brunswick, who played in the tournament's last threesome with the two teenagers. "It's nice to see some junior players coming up who can play. They're both more than respectable players."
Rondeau, who carded a two-day total of 163 to finish fourth, admitted it was a struggle to keep up with Rancourt and Merrill.
"It's a different kind of pressure to play with kids that age who hit the ball that far," she said.
Rancourt routinely drove the ball 250 yards off the tee.
"I was playing catch-up all the time," said Rondeau, a three- time SMWGA senior champion. "I struggled with my short game, and that's usually a strength of mine. It just didn't show up today."
Rancourt, who fired a 3-under-par 71 in Monday's opening round, finished Tuesday's round with a flourish. She drained a 15-foot uphill putt for an eagle on the par-5, 394-yard ninth, which served as the final hole for the tournament in front of a large gallery.
"I tend to play better when there's an audience for some reason," said Rancourt, who attended Waynflete School through ninth grade before going to the Leadbetter Academy. "I don't know why. I guess I like a big gallery."
It is the first summer Rancourt has played in SMWGA tournaments.
"I started playing this summer and I loved it," she said. "They're awesome. They're just so supportive, and they're really nice.
"I played in three events to qualify for this, and everyone I play with I felt I was out there with a bunch of my friends."
Leslie Guenther, the 2005 SMWGA champion from Norway Country Club, carded matching 81s to finish third in the tournament with a two-day total of 162.
Mary Brandes, a two-time champion from The Woodlands in Falmouth, recorded matching 82s to finish fifth at 164.
Laurie Hyndman, a six-time champion from The Woodlands, is recovering from surgery and was unable to defend her title.
Rancourt and Merrill will compete in the Maine women's amateur Monday through Wednesday at Bangor Municipal. They'll also play in the state junior tournament, which will be held Wednesday through Friday at Val Halla Golf Club in Cumberland.
Their third-round score at the women's tournament will serve as Wednesday's qualifying round for the final two days of match play at the junior tournament.
A year ago, Rancourt beat Merrill in match play to capture the junior title.