The Rangers said Tuesday that Gosselin, Middlebrooks, right-hander Paul Espino and outfielder Jared Hoying cleared waivers and were assigned outright to the Triple-A team.
Gosselin, acquired from Pittsburgh on a waiver claim Aug. 12, hit .125 in 12 games over three stints with the team. Middlebrooks led Round Rock with 23 homers and 64 RBIs before being called up by the Rangers on Sept. 1, and then hit .211 in 22 games.
Espino had a 5.68 ERA in six relief appearances after being acquired from Milwaukee in an Aug. 26 trade. Hoying hit .222 with one homer in 36 games.