The Reading Fightin Phils dropped their series finale to New Hampshire on Sunday 7-5 in 12 innings at FirstEnergy Stadium.
The Fightins fell behind 4-1 before rallying to tie the game at 4-4 and force extra innings.
The Fisher Cats took a 5-4 lead in the 11th, but Derek Mitchell's two-out, two-strike RBI single tied the game at 5-5.
But Brad Glenn's two-run home run in the 12th proved too much for Reading to overcome.
New Hampshire hit four homers on the day, two by Glenn.
Anthony Hewitt hit his second homer in as many days for the Fightin Phils. Jim Murphy had three hits and an RBI.
Reading (38-54) will open a three-game series with Trenton in Baseballtown Monday night at 7:05pm.
Alex Rodriguez will rehab for the Thunder in the game, and IronPigs All-Star second baseman Cesar Hernandez will play center-field for Reading.