Foster began his professional career with the New York Giants in 1898 at the age of 20. He batted .268 with 30 hits, six doubles and nine RBIs.[1]
In 1899 Foster hit .296 with 89 hits, nine doubles, seven triples, three home runs 57 RBIs and seven stolen bases in 84 games. Foster established a career high in batting average.[1]
In Foster's final season with the Giants in 1900 he hit .262 with 22 hits, three doubles and 11 RBIs in 31 games.[1]
Washington Senators
1901 was a career year for Foster with the Washington Senators. He hit .278 with 109 hits, 16 doubles, nine triples, six home runs, 54 RBIs and 10 stolen bases in 103 games. Despite his good play Foster was released by the Senators on September 9, 1901.[1]
Chicago White Stockings
The day Foster was released by the Senators, the Chicago White Sox of the American League signed Foster. He finished the season with Chicago batting .286 with 10 hits, two doubles, two triples, one home run and six RBIs. He finished the season with career highs in at bats, runs, hits, doubles, triples, home runs, RBIs, stolen bases, walks, on-base percentage, slugging percentage and on-base plus slugging.[1]
In 262 games in the major leagues, Foster hit .281 with 260 hits, 36 doubles, 20 triples, 10 home runs and 137 RBIs.
Yale men's basketball coach
In addition to playing professional baseball, Foster also coached the Yale Universitymen's basketball team for the 1912–13 collegiate basketball season.[2] The Bulldogs finished with a 5–7 record in his lone season at the helm.[2]
