Sometime in the late afternoon on the third of October, 2012, Chicago White Sox reliever Leyson Septimo struck out shortstop Cord Phelps for the last out in a 9-0 romp to end yet another in a series of disappointing seasons for the Cleveland Indians.

The loss meant that the Tribe would finish the 2012 campaign with an unsightly record of just 68-94 and hardly a reason at all for optimism. The club featured an offense that lagged significantly below average at -25 wRAA, while the pitching staff was even less desirable, ranking just 26th in pitcher’s WAR. By late September, with just a few games remaining on the schedule, the organization had announced that manager Manny Acta had been fired, and that bench coach Sandy Alomar Jr. would finish the season as the team’s interim manager.

But despite these disappointments from multiple fronts, the Indians still managed to make history in 2012.

Since 1960, when data for batter handedness for each plate appearance first becomes available to Retrosheet, no other team has sent more left-handers to the batter’s box than last year’s Indians club. With over 71 percent of their team’s at-bats occurring from the left side of the plate, the 2012 Tribe far exceeded the previous record of 65 percent they had established just a year prior.

Most left-handed lineups since 1960

Rank Team Year LHB PA% wRC+ 1 Indians 2012 71.7 97 2 Indians 2011 65.2 98 3 Padres 1981 64.7 91 4 Dodgers 1991 63.3 97 5 Phillies 1993 62.1 105 6t Padres 1982 61.9 90 6t Mariners 2012 61.9 87 8 Yankees 2007 62.3 119 9 Tigers 1977 61.3 94 10 Twins 2001 61.2 99 11t Mariners 2011 60.4 80 11t Red Sox 2011 60.4 116 13 Yankees 2009 60.0 117 14 Phillies 1995 59.8 88 15t Tigers 2003 59.4 95 15t Yankees 1969 59.4 86

The 2012 Indians lineup featured four left-handed starters who saw regular playing time throughout the season with Shin-Soo Choo, Michael Brantley, Jason Kipnis and Casey Kotchman all seeing at least 500 plate appearances. Switch-hitting Carlos Santana and Asdrubal Cabrera saw most of the at-bats at shortstop and catcher, while the plurality of playing time at third base and designated hitter went to left hand-hitting Jack Hannahan and Travis Hafner.

Shelley Duncan saw the most playing time of all the Tribe’s right-handed batters with just 264 plate appearances, while the bulk of the remaining at-bats in left field were delegated to veteran left-handed hitter Johnny Damon.

All of this amounts to something baseball has not witnessed for at least the duration of the past 50 years, and possibly throughout all of baseball history: Almost three-quarters of all Indians at-bats were left-handed.

Only the San Diego Padres came close to this unusual feat, when they entrusted 65 percent of their at-bats to left-handers during the course of the 1981 season. That offense fared considerably worse than the recent Indians squads, however, struggling with a wRC+ nine percent below the league average that year. Although, most of that damage was wrought by their right-handed Gold Glove shortstop Ozzie Smith, with his insufferable 65 wRC+ in a league-leading 500 plate appearances. The team as a whole finished in last place (in both halves) for that strike-shortened season with a forgettable overall record of 41-69.

It would seem that the Yankees lineups from just a few years ago, as well as the more recent 2011 Red Sox, were the only offenses that managed to produce at an elite level with such a severely disproportionate amount of their hitting occurring from the left side. All three rosters managed a formidable wRC+ of at least 115.

The 2011 Red Sox featured some extremely dangerous left-handed threats of the American League that year with Adrian Gonzalez, David Ortiz, and Jacoby Ellsbury all terrorizing pitchers in the neighborhood of 150 wRC+ for that season. Carl Crawford and J.D. Drew combined to undermine some of that left-handed onslaught, by simultaneously having the worst seasons of their careers. Ultimately the Red Sox would miss the playoffs in 2011, despite winning 90 games that year.

The 2007 Yankees and their 2009 world champion successors, on the other hand, presented a less concentrated left-sided attack led by Robinson Cano, Hideki Matsui, and Johnny Damon, in addition to the always dangerous switch-hitting Mark Teixeira, Nick Swisher and Jorge Posada. Together this group combined to produce the eighth most left-handed lineup of the last 50 years, while also boasting one of the more succesful offenses of the decade. (The 2007 Yankees also featured Bobby Abreu and Jason Giambi from the left side.)

While these teams fared extremely well with an inordinate amount of southpaws in their lineup, it is not impossible to achieve the same results with a glaring absence of left-handers:

Least left-handed lineups since 1960

Rank Team Year LHB PA% wRC+ 1 Padres 1970 12 91 2 Padres 1969 14 75 3 Padres 1977 17 93 4 Rockies 1993 17 85 5 Astros 1998 18 113 6 Astros 2001 19 101 7 Braves 1979 19 83 8 Braves 1967 19 95 9 Astros 1996 19 98 10 Dodgers 1975 20 96 11 Padres 1971 20 81 12 Marlins 2010 20 92 13 Braves 1980 20 86 14 Brewers 1978 20 117 15 Dodgers 1979 21 104

Both the 1998 Houston Astros and the 1978 Milwaukee Brewers clubs featured an abnormally low lefty presence in their lineups and still hit well over 15 percent above league average.

If you’ll remember, all three of the Astros’ infamous “Killer Bees” hit from the right side of the plate, and all three were extremely dangerous. In 1998 Jeff Bagwell led the trio with a fearsome 162 wRC+, while Craig Biggio (145) and Derek Bell (129) weren’t too far behind. They were joined by another powerful right-handed bat that season when Moises Alou and his 157 wRC+ came over from the Marlins via offseason trade.

Only the third baseman, Bill Spiers, provided regular at-bats from the left-side for the Astros that year, and he wasn’t quite able to reach 500 plate appearences before the season’s end. The switch-hitting Carl Everett provided the team’s only source of left-handed power that year, amassing most of his 125 wRC+ in his 438 plate appearances as a left-handed hitter.

But while the ’78 Brewers and ’98 Astros performed at an elite offensive level with limited contributing left-handed at-bats, the upstart Padres teams of the late 1960s were not nearly as fortunate. In their inaugural season in 1969, the brand new Padres franchise combined for a team wRC+ of just 75 while setting the record for the lowest amount of left-handed plate appearances in a single season with just 14 percent. Backup third baseman Van Kelly led all left-handers in plate appearances for the Padres with just 222 that year. In the following season Kelly would see even less playing time, which meant the Friars saw even fewer left-handed at-bats with just 12 percent, establishing the record that still holds today.

All this may lead one to wonder if the amount of left-handed hitters on a team affects its performance.

Effect of left-handedness

Expanding on some data I originally ran for SBNation’s Cee Angi, I found that there seems to be little relationship between strength of offense and a lineup’s left-handedness. A test on the 1,372 team-seasons from 1960 and 2012 reveals very little correlation (r = .08) between a team’s wRC+ and the percentage of its plate appearances that occurred from the left side.

Teams that delegate less than 25 percent of their at-bats to left-handers typically fare no worse than teams who feature more traditionally balanced lineup cards. However, teams that have been featured unusually high amount of left-handed at-bats tend to be slightly more successful than average:

LH PA% average wRC+ # teams > 25% 95.1 54 26%-30% 95.9 132 31%-35% 95.1 215 36%-40% 94.2 260 41%-45% 95.7 285 46%-50% 96.3 219 51%-55% 98.6 136 >55% 96.4 53

This shouldn’t be too surprising. Left-handed hitters are simply more successful as a group than their right-handed counterparts. So more left-handers will more often mean more success at the plate. This doesn’t mean that adding left-handed hitters will improve your team necessarily, but that simply adding better hitters to your team will improve your production.

What’s also interesting from our first table is that a third of the 15 most left-handed teams of the past 50 years have occurred in the past two seasons. Aside from the aforementioned Red Sox and Indians teams, the forlorn Mariners lineups of the past two years also ranked in the top 15. Nine of these sixteen teams occurred in the 2000s and there was only one team-season to represent the 1960s (and that occurred at the very edge of the decade in 1969).

I’m not entirely sure how to explain this. Could it be that front offices are more willing to trot out unbalanced rosters these days? Was there some sort of conventional wisdom prejudice against having too many left-handers in a lineup in the ’60s and ’70s? Or are left-handed hitters simply more available in recent years?

While it’s true that the percentage of left-handed at-bats in baseball has increased since the 1960s, that number has remained relatively static over the past 25 years:

The 2013 Indians and beyond

For 2013, the Tribe has lost left-handed Shin-Soo Choo, and gained right-handed hitting Drew Stubbs. The Indians also will be replacing some of the left-handed at-bats from Casey Kotchman with the switch-hitting of Nick Swisher, although I doubt anyone could blame them for that. It’s not unreasonable to expect more of these egregiously left-handed lineups in the future, but it’s very likely that we will not see a phenomenon like the 2012 Cleveland Indians for a very long time.

References & Resources

Thanks to Retrosheet, Baseball-Reference and Fangraphs. All LH PA percentages include post-season numbers. wRC+ figures include pitchers hitting.