In the 1975 World Series against the Boston Red Sox, Eastwick won Games 2 and 3 and also earned a save in Game 5 as the Reds won the series in seven. In Game 6 he gave up a three-run home run to Bernie Carbo that tied the game, which the Red Sox won in twelve innings. In 1976, Eastwick had his best season, going 11–5 in relief with a 2.06 earned run average. He also led the league in saves and won the NL Fireman of the Year award.[1] The Reds won their second consecutive World Series title.
Eastwick was dealt to the Cardinals for Doug Capilla at the trade deadline on June 15, 1977, as a result of a contract dispute with Reds management. His desire to become a free agent by not signing a contract with any team for the remainder of the season precluded him from being sent to the New York Mets in the Tom Seaver trade.[2] Eastwick signed a five-year, $1.2 million deal with the Yankees at the Winter Meetings on December 9, 1977. He joined a bullpen which already had Sparky Lyle, Dick Tidrow and Goose Gossage the last of whom had signed for $2.7 million two weeks earlier.[3] Eastwick's time with the Yankees lasted until the day before the trade deadline on June 14, 1978, when he was sent to the Philadelphia Phillies for Jay Johnstone and Bobby Brown.[4] He spent two seasons with the Phillies, posting a 4.90 ERA in 1979 and was released. Eastwick then pitched for the Kansas City Royals in 1980 and the Chicago Cubs in 1981 before retiring.