Our "MLB Quiz of the Day" series on the best player to wear each number (based on WAR, courtesy of Baseball-Reference) continues with the focus shifting to uniform numbers in the 40s.

An important note before getting started: A player is only considered eligible for whichever number he wore for the most seasons during his career. For example, Roger Clemens is considered only for No. 21, which he wore for 15 seasons, and not for No. 22 (nine seasons) or No. 12 (one season). That said, this quiz isn't designed to test your knowledge of how many seasons a player wore a certain number, so operate under the assumption that if a player is listed as a possible response, then he is indeed eligible for that specific number.

Other best-player-by-number quizzes:
• Nos. 0-9
• Nos. 10-19
• Nos. 20-29
• Nos. 30-39

Let's get started below: