In 1977, Eastwick got into a contract dispute with the Reds' front office and was traded in June, to the St. Louis Cardinals. In 1978, he joined the New York Yankees after signing a five-year, $1.1 million deal. The Yankees then traded him in June to the Philadelphia Phillies, where he spent the next two seasons. Eastwick posted a 4.90 ERA in 1979 and was released. He then pitched for the Kansas City Royals in 1980 and the Chicago Cubs in 1981 before retiring.