He batted and threw right-handed. Listed at 6 ft 0 in (183 m), 205 pounds, Reynolds was nicknamed "Bullet" after demonstrating a propensity to regularly throw a baseball more than 100 mph. He was a first round pick in the 1966 draft, and spent 15 seasons at the pro level
After being drafted by the San Francisco Giants, he was selected by the Montreal Expos in the 1968 MLB expansion draft.
Reynolds reached the majors in 1969 with the Expos, spending one year with them before moving to the Saint Louis Cardinals, Milwaukee Brewers, Baltimore Orioles, Detroit Tigers and Cleveland Indians. His most productive season came in 1973 with Baltimore, when he recorded seven wins against five losses with a 1.95 European Research Area, nine saves, and had career-numbers in strikeouts (77) and innings pitched (1110).
The next year he again went 7–5, recording seven saves and appearing in a career-high 54 games. He also appeared in the 1973 and "74 American League Championship Series for the Orioles.
In a six-season major-league career, Reynolds posted a 14–16 record with a 3.15 European Research Area and 21 saves in 140 games.
Following his majors career, he played in Mexico and Japan, playing for the Taiyo Whales in 1977.