 He continued to take a turn in the Kansas City rotation for the next two seasons and won a dozen games each year for the struggling Athletics, but he also led the American League in games lost (20) in and home runs allowed (40) in .When he lost his first six decisions of , Peña was waived to the Tigers, where he became an effective relief pitcher through the end of .In , Peña registered a career-high eight saves for the Tigers and Indians with an earned run average of 3.59, but Cleveland sent him back to the minors in 1968 and Peña would not return to the majors until June 1970 when he signed as a free agent with the Pirates.