An outfielder, Schoonmaker was signed to a $30,000 bonus contract by the Washington Senators of Major League Baseball in 1955 after a standout career at the University of Missouri.

However, his career was hampered by the Bonus Rule, which compelled him to spend his first two years as a professional on the Washington roster.

Schoonmaker threw and batted right-handed, stood 5 feet 11 inches (1.80 m) and weighed 190 pounds (86 kg).

[1] That offseason, he underwent surgery after an errant sliver of metal injured his left eye while he was working at a construction job.

All told, Schoonmaker registered nine hits in 69 MLB at bats, including one double, triple and one home run.