Clearwater kept it close at Charlotte on Sunday, but a leadoff error led to the game-winner in the 12th inning as the Threshers suffered the series loss, falling 4-3 at Charlotte Sports Park.
The Threshers (63-64, 25-32) drop to 3.5 games back of the Dunedin Blue Jays for the second playoff spot in the FSL North, with just 13 games remaining.
Austin Bossart gave Clearwater a 1-0 lead in the second inning on Sunday. Grenny Cumana reached on a two-out infield hit, and Bossart followed with a double to center to score Cumana and push the Threshers out to the early advantage.
Charlotte (63-61, 32-24) brought it even in the fourth, loading the bases on a single, error, and walk. Thomas Milone's sacrifice fly tied the ballgame at one.
The Stone Crabs went ahead an inning later, when Lucius Fox doubled off Harold Arauz with one out, and Michael Brosseau singled him in.
Arauz exited after 4.1 innings in the spot start, allowing two runs (one earned) on six hits and a walk. Aaron Brown struck out three and allowed just a walk in 1.2 scoreless innings of relief.
Blake Quinn took over in the seventh, and the Stone Crabs placed the first two on following a walk to Brosseau and a Ryan Boldt single. Bossart nabbed Brosseau attempting to steal third, and Quinn induced Kevin Padlo to ground out to short before a walk to David Olmedo-Barrera loaded the bases.
Peter Maris then singled to right, scoring Bolt to put the Stone Crabs up 3-1.
Clearwater battled back in the late innings for the fourth-straight day.
With Jose Gomez aboard at first and two outs, Edgar Cabral attacked the first offering from Dalton Moats and sent a two-run, game-tying home run to left field to bring it back even at three apiece.
Luke Leftwich hurled three hitless innings in relief and JD Hammer worked around pair of baserunners in the 11th, as the teams remained deadlocked into the 12th.
Seth McGarry (1-3) took over on the hill, and Boldt reached on an error on Cumana at second to open the inning. With one out, Boldt took off and Olmedo-Barrera singled to put the winning run at third.
Clearwater deployed a five-man infield, but Maris lined one over short to end it.
After an off-day on Monday, the Threshers will return home to host the red-hot Fort Myers Miracle on Tuesday at 7 p.m. The game will be broadcast live on threshersbaseball.com starting at 6:45 p.m.
This story was not subject to the approval of the National Association of Professional Baseball Leagues or its clubs.