Kalie Hughes was dominant both on the mound and at the plate for the Hawks.
Hughes pitched a one-hit complete game with seven strikeouts and only one walk.
At bat, Hughes went 4-for-4 with three triples, drove in two runs and scored a run for Kelly.
"Kalie pitched a great game and gave up their only hit on a changeup," Kelly coach Rhonda Ratledge said. "We have been working and working on that pitch all year long. She has had a good looking changeup in practice hitting the outside corner, but today she just floated it right down the middle. Kalie has only allowed two hits in 17 innings the last couple of game, and she seems to be clicking at the right time."
Hughes credited working on the fundamentals both on the mound and at the plate.
"I have been working hard staying after practice getting that extra throwing time in," said Hughes. "I focused on improving my fundamentals and just throwing like I know how to."
Hughes, Brittany Ponder and Katee Moore were a combined 6-for-8 at the plate with six RBIs, seven runs scored, five walks and two stolen bases.
The Hawks pinned the loss on Carlee Vancil.
"She is a quick pitcher and a very good pitcher at that," Hughes said. "I just focused on keeping my weight back and getting a hit for the team."
Vancil had nine strikeouts and allowed only six hits, but eight walks came back to haunt the Royals.
"We have been a good hitting team all year," Kelly coach Rhonda Ratledge said, "and although their pitcher is very good, I knew we could put the ball in play. We had some good swings up there and we made some things happen on the bases once we got on."
The big hit for the Hawks was a two-out solo home run by Ponder in the top of the second inning.
"It felt great to get the home run for the team," said Ponder. "I kept my head in and shoulder up and made level contact. The hours and hours of practice gets you into a routine up at the plate, and I just executed what I have been taught for years."
Ratledge was impressed by her senior's blast.
"It was a sweet hit," Ratledge said. "Brittany is little, but is mighty with the stick. She made connection with the ball and followed all the way through like your taught and just sailed it over the fence."
Twin Rivers (8-6) made some crucial errors out in the field that opened the door for Kelly. The Hawks scored three runs on pass balls and three more runs on two fielding errors.
After the Ponder home run in the top of the second, Moore drew a walk. Hughes promptly laced a hard single to right field which went right through the legs of the fielder all the way to the fence. Moore scored from first and Hughes came all the way around the bases to score.
Kelly led 5-0 after two innings of play.
Kelly enacted the mercy rule in the fifth inning on a fielding error and RBIs by Moore on a triple and Hughes on a single.
Kelly (24-6) advances to the quarterfinals at the Ballwin Athletic Fields in Ballwin on Saturday to face Fatima. Fatima (17-10) defeated Orchard Farm 4-0 to in their sectional meeting.
KELLY 11, TWIN RIVERS 0
WP -- Kalie Hughes; LP -- Carlee Vancil. 3B -- Hughes (K) 2, Katee Moore (K); HR -- Brittany Ponder (K). Multiple hits -- Kelly, Hughes 4-4. Records -- Kelly 24-6, Twin Rivers 8-6.