At the MLB level, Hoerner played for the Houston Colt .45s (1963–1964), St. Louis Cardinals (1966–1969), Philadelphia Phillies (1970–72, 1975), Atlanta Braves (1972–1973), Kansas City Royals (1973–1974), Texas Rangers (1976), and Cincinnati Reds (1977).

In this particular game, Houston manager Harry Craft used a starting lineup of nine rookies, including Jerry Grote (20), Joe Morgan (20), Rusty Staub (19), and Jimmy Wynn (21).

On July 22, 1966 at Wrigley Field he hit his only major league home run, a three-run shot, against Hall of Famer Ferguson Jenkins.

During 1971 that year he gave up Willie Mays' major league-leading 22nd and last career extra-inning home run at Candlestick Park.

Hoerner held All-Stars Bobby Bonds, Johnny Callison, Tommy Harper, Ed Kranepool, Joe Pepitone, and Bill White to a .070 collective batting average (5-for-71).

In 1985, Hoerner was acquitted of reckless and negligent operation of a motorboat, charges stemming from a collision on the Lake of the Ozarks that killed two 25-year-old boaters.