career All-Star nod. Despite a 2–14 record in , Knowles enjoyed career highs in saves (27), appearances (71) and innings pitched (119.1). Oakland A's On May 8, 1971, the first-place Oakland Athletics acquired Knowles and Mike Epstein for Frank Fernandez, Paul Lindblad, and Don Mincher. Knowles only allowed four of 35 inherited runners to score, and earned seven saves and five wins out of a bullpen that already included Rollie Fingers and Bob Locker. The A's won the American League West by 16 games over the Kansas City Royals, but were swept by the Baltimore Orioles in the 1971 American League Championship Series. Knowles' only series appearance came in game three. In , Knowles went 5–1 with a 1.37 ERA and 11 saves, but he was lost for the postseason due to a broken thumb. 1973 World Series Knowles made five starts for the world champion A's in , pitching his only complete game shutout against the Boston Red Sox on August 14. The Athletics repeated as American League champions, and faced the New York Mets in the 1973 World Series. Knowles appeared in all seven games of the World Series, pitching innings without giving up an earned run, and earning the saves in games one and seven. He is one of only two pitchers to appear in all seven games of a World Series (the other pitcher being Brandon Morrow, in ). In his 1980 autobiography, Athletics manager Alvin Dark recalled that Knowles "was having a bad year" in 1974. In one game where Knowles struggled, Dark came to the mound to remove him from the game. Knowles argued with him on the mound, protesting that he would not get in shape unless he was able to pitch him more often. "Why don't you trade me?" he asked Dark when they got back to the dugout. "Because nobody wants you, that's why!" Dark retorted. Knowles went 3–3 with a 4.22 ERA and blowing two of his five save opportunities. His .296 batting average against was the highest in the Oakland bullpen. Regardless, the A's won their third World Series in a row in ; however, Knowles did not make a post-season appearance. Shortly after the World Series, he, Bob Locker and Manny Trillo were dealt to the Chicago Cubs for Billy Williams. Final years Knowles inherited the closer role in Chicago, saving 15 in and nine in . Shortly