At the start of the 1929 season, the New York Yankees and Cleveland Indians innovated baseball, starting the season with numbers on the back of their players jerseys for easy identification. While numbers had been experimented with prior to the season, they were mostly smaller and located on the arms, meant primarily for umpires and the official scorers. The numbers on the back of the jersey were for fans in the stands to clearly tell who each player was, a move that scorecard salesmen had been pushing
for years.
Some current baseball traditions remain from that era. The Yankees famously assigned numbers based on the lineup, with the backup catchers taking 9-10 respectively. Pitchers and bench players wore higher numbers, which is why pitchers generally don’t take single digit numbers. Blake Snell (no.4) became the first pitcher to play in the All-Star game and win a Cy Young award while wearing a single digit number in MLB history in 2018. Higher numbers were long assigned to fringe invitees to Spring Training or marginal players, although that tradition has declined sharply over the last twenty years.
0 and 00 is the least assigned player number below 50 in the history of the MLB. To date, no team has ever retired 0 or 00. The reasons are relatively simple. Youth baseball is loathe to give out 0 or 00 because it is easy to apply a derogatory connotation to it, and many MLB players chose their number based on earlier team numbers from their youth. However, that seems to be changing recently. In 2026, 10 players wore 0 or 00 at the major league level, down from 13 in 2025. In fact, more players have worn 0 or 00 since 2020 than in other 91 seasons combined.
Who is the most successful player to wear 0 or 00 as a member of the Toronto Blue Jays?
WWIB: Andrés Giménez 2025-2026 (1.3 bWAR)
Giménez was a former Mets top prospect who was traded to Cleveland as part of a package for Francisco Lindor and Carlos Carrasco in 2021. He had a breakout season in 2022, hitting .297/.371/.466 while earning a Gold Glove at second. It prompted the Guardians to sign him to a backloaded 7 yr/$106.5M contract in the offseason. He won two more Gold Gloves, but his offense significantly declined. The Jays acquired him and Nick Sandlin in December 2024 for Spencer Horwitz and Nick Mitchell. The move was highly questioned at the time, especially considering that the main issue the 2024 last place Jays suffered from was a lack of offense. Giménez’ offensive woes continued in 2025 but his defense was as good as advertised. When Bo Bichette was injured following a collision at home plate against the Yankees on Sept 6, Giménez became the primary shortstop for the remainder of the regular season and the post-season. Many Jays commentators saw the Giménez trade as a harbinger that the club was ready to move on from Bichette, and with the emergence of Ernie Clement as an elite defender and everyday starter, the Jays were able to deploy elite defense up the middle. Giménez has three more years and a club option remaining on his contract.
Other notable Jays to wear 0 or 00 were Taijuan Walker in 2020 (1.0 bWAR), Al Oliver in 1985 (-0.6 bWAR) and Cliff Johnson also in 1985 (-0.1 bWAR).
