Barnes (3-2) allowed one run on a walk and a wild pitch in 0.2 innings to take the loss Thursday in a 1-0 loss to Tampa Bay.
Barnes came on to start the ninth inning of a scoreless tie and quickly retired Austin Meadows and Yandy Diaz. Things subsequently unraveled after Barnes walked Manuel Margot, who promptly stole second and advanced to third on Christian Vazquez's errant throw. Margot later came in to score when Barnes bounced a wild pitch in front of Vazquez. Barnes, who has allowed a run in three of his last four outings, still owns a 2.90 ERA and 0.84 WHIP on the season while converting 15 of 18 save chances.