Donald Louis Newhauser (born November 7, 1947) is an American former professional baseball pitcher.

Listed at 6 feet 4 inches (1.93 m) and 200 pounds (91 kg), he threw and batted right-handed.

[4] The following season, Newhauser made his MLB debut in June, and appeared 31 games (all in relief) with the 1972 Red Sox, compiling a 4–2 record with a 2.43 earned run average (ERA) while recording 27 strikeouts in 37 innings pitched.

[5] Overall, he made 42 major league appearances, all in relief with the Red Sox, registering a 2.39 ERA and 37 strikeouts in 52+2⁄3 innings pitched with a 4–3 record.

[5] Newhauser pitched in Minor League Baseball for the Red Sox organization through 1975, then finished his career in 1976 with the Charleston Charlies, a Triple-A affiliate of the Pittsburgh Pirates.