Eleven players in A’s franchise history have worn the Number 42 (not counting the games in recent years where every player dons that number). They are:
Ed Cihocki (1932), Dick Fowler (1941), Ozzie Van Brabant (1954), George Lauzerique (1967), Juan Pizarro (1969), Tommy Davis (1970), Tony LaRussa (1971), Kelvin Moore (1983), Dave Henderson (1988-1993), Jeff Schaefer (1994), and Buddy Groom (1996-1997).
The first "A" to wear the number (post-Jackie's debut 66 years ago today) was Ozzie Van Brabant, who appeared in a total of 11 games in his brief career.
George Lauzerique was another to wear the number 42. He debuted against the Angels on September 17, 1967 and pitched seven innings in a 3-2 loss, in a game that featured Reggie Jackson’s first big-league homerun.
Dave Henderson sported the Number 42 in more games than any other player in franchsie history (702), including four games on April 15 (1988-1991), and went 2-for-15 with a homerun (on this date in 1989).
Buddy Groom, who pitched in 301 games over four seasons with Oakland, including a league-high 76 games in 1999, was the last Athletic to wear 42 before it was retired for good on April 15, 1997 by all major league teams. Players that entered the season wearing that number were allowed to keep it, including Groom who switched anyways to 24, a number that has since been retired by the A’s in honor of Rickey Henderson.