Only four teams since 1900 have gone through an entire season without a single lefthander:
- 1901 Boston Beaneaters (69-69) - used five pitchers in 140 games.
- 1903 New York Giants (84-55) - used seven pitchers in 142 games.
- 1918 Philadelphia Phillies (55-68) - used eleven pitchers in 125 games.
- 1934 Chicago White Sox (53-99) - used fourteen pitchers in 153 games.
- 1974 Montreal Expos (79-82) - 81 BF by Balor Moore and Terry Enyart
- 2006 Arizona Diamondbacks (76-86) - 113 BF by Randy Choate, Doug Slaten, and Terry Mulholland
- 2000 Kansas City Royals (77-85) - 240 BF by Jose Rosado, Scott Mullen, Paul Spoljaric, and Tim Byrdak
- 1993 Los Angeles Dodgers (81-81) - 275 BF by Omar Daal and Steve Wilson
- 1983 Toronto Blue Jays (89-73) - 276 BF by Dave Geisel and Stan Clarke
- 1954 Baltimore Orioles (54-100) - 287 BF by Bob Kuzava, Billy O'Dell, Dave Koslo, Dick Littlefield, and Jay Heard
- 2001 Milwaukee Brewers (68-94) - 287 BF by Ray King, Lance Painter, and Valerio de los Santos
- 1957 Boston Red Sox (82-72) - 294 BF by Dean Stone, Frank Baumann, and Jack Spring
- 1996 Chicago Cubs (76-86) - 320 BF by Bob Patterson and Larry Casian
- 2000 Houston Astros (72-90) - 343 BF by Billy Wagner, Yorkis Perez, and Wayne Franklin
- 1996 New York Mets (71-91) - 350 BF by John Franco, Bob MacDonald, and Pedro Martinez
With six games left to play, the 2009 Cardinals duo of Trever Miller and Dennys Reyes has faced a combined 335 batters.
This year's Cardinals and a couple other teams above spoil my ending a bit, but it sure looks to me like the answer to "Who needs lefties?" is "winning teams."