Triplett is now 16-8 on the season after a hard fought 3-2 victory over class AAA McMinn County in Athens to wrap up regular season play.
Polk County (22-11) will open District 5-AA play Monday as the No. 2 seed and will entertain third-seeded McMinn Central at 5:30 in Benton.
After setting the Lady Cherokees down in order in the first three innings, Triplett scattered six hits and allowed just one earned run Thursday, striking out four and not walking a batter.
The Lady Wildcats got on the board first when Lily Cuzzort led off the top of the second with a single and Caroline Jenkins followed with a double to bring her in.
Polk pushed the advantage to 3-0 with a pair of fourth inning runs. Triplett reached on an error and Brianna Muller followed with a walk. Sydney Rogers sacrificed the two up a base but a two-out double by Danielle Harvey brought the pair around to score.
McMinn County answered with both of its runs in the bottom of the fourth, thanks in part to a pair of Lady Wildcat errors. The hosts threatened again in the bottom of the seventh, getting a pair of runners on, but Triplett closed the door with back-to-back strikeouts to end the game.