The Rays have been involved in 46 one-run games, which ranks second in the AL behind the Mariners, and they are 20-26 in those games.
Tampa Bay has lost 13 of its last 16 one-run games and is 8-22 in one-run games since May 28 after starting the season 12-4.
"It has not been good," manager Joe Maddon said before Thursday's game. "We have really be unable to get the necessary hit and we've had opportunities, the latter part of games and in extra innings against some better relief pitchers, we've had a hard time. That's just being straight up, that's what's happened.
"We've had guys on the bases. We've had guys at the plate. It's not just one or two guys, it's the entire group, we just have not been good at that play. But, that does not mean we can't still be good at that play. ... At some point, it switches or flips."