The Red Sox designated Kahnle for assignment Wednesday.
Chris Cotillo of MassLive.com relayed after Tuesday's 8-1 loss to the Nationals that Kahnle would be DFA'd, and the move has now been made officially after Boston acquired infielder Brett Harris in a trade to take the reliever's spot on the 40-man roster. After signing a minor-league deal with Boston late in spring training, Kahnle moved up to the big leagues on June 4 and turned in an 8.00 ERA, 2.00 WHIP and 5:6 K:BB across nine innings over eight appearances out of the bullpen.