Stroman and Bell, who started Thursday night's game for their respective teams, both wear single-digit uniform numbers -- No. 6 for Stroman and No. 4 for Snell. According to ESPN Stats & Information, their pitching matchup at Tropicana Field on Thursday night marked the first time two single-digit starters had faced off since Sept. 14, 1941, when Johnny Hutchings (who wore No. 5) of the Boston Braves opposed Johnny Schmitz (No. 7) of the Chicago Cubs.
According to ESPN Stats & Info, there were at least seven other single-digit showdowns in the 1930s and '40s, including three in 1939 alone involving Cleveland Indians fireballer Bob Feller (who wore No. 9 that season, although he would later become more identified with No. 19) and Chicago White Sox left-hander Eddie Smith (No. 6).
Single-digit numbers have traditionally been uncommon for big league pitchers, in large part because early uniform numbers were often based on where players hit in the batting order and pitchers usually hit last.
But there has been a bit of a single-digit mound movement in recent years, as a small but growing fraternity of pitchers has embraced the solo numerals. In addition to Stroman and Snell, other examples currently on MLB rosters include Matt Belisle of the Minnesota Twins (No. 9); Carl Edwards Jr. of the Chicago Cubs (No. 6); Mike Leake of the St. Louis Cardinals (No. 8); Adam Ottavino of the Colorado Rockies (No. 0); and Clayton Richard of the San Diego Padres (No. 3).
Most of these pitchers have personal reasons or superstitions for preferring their single-digit numbers. Stroman, for example, wears No. 6 because his grandmother's birthday is March 6. Leake wears No. 8 because it's the number he wore while playing at Arizona State. Belisle wore No. 9 in Little League and high school and wanted to recapture his childhood enthusiasm for the game by wearing his old number. And Ottavino wears No. 0 because his surname begins with the letter O.