Plagued by struggling starting pitching, the Twins have looked to bolster their pitching staff during the past two offseasons. Before the 2013 season, Minnesota brought in Mike Pelfrey and Kevin Correia. This past offseason, the Twins signed Phil Hughes and Ricky Nolasco. Three of these four acquisitions had a common thread: They came from the National League.
Free agents are more league-conscious than ever in today’s MLB. Because of the designated hitter, it is presumably more difficult to pitch in the American League than it is in the National League. Because NL pitchers hit, one-ninth of the batting lineup is far weaker in the senior circuit.
The assumption is that pitchers aren’t great hitters. This is true. Since the DH was conceived in 1973, 578 pitchers have recorded over 100 plate appearances with only 61 compiling batting averages over .200 and none above .283 (Micah Owings). This season, there are 69 pitchers with 20 or more at-bats, and all but 12 have averages below the Mendoza Line.
So for over 40 years now, the National League lineup has contained an automatic out that American League lineups do not.
For starting pitchers, easier outs mean easier innings, fewer struggles with the bottom of the order, lower pitch counts and, in theory, fewer runs allowed, lower ERAs and more offseason money.
The perception is that AL teams should steer clear of NL free agents. This, of course, is based on the idea that a designated hitter is twice as productive as a pitcher at the plate.
Leave it to the Twins to become the poster child for how dangerous NL pitchers can be. Pelfrey, Correia and Nolasco – especially Nolasco – have struggled since being signed to a combined $74 million in contracts.
This local trend begs the questions: How frequently do National League free agent pitchers fail in the American League? And do American League free agent pitchers succeed in the National League?
To find out, I recorded every instance of a free agent starting pitcher switching leagues over the past eight offseasons. Then I compared each pitcher’s ERA in their years surrounding free agency. For example, Ricky Nolasco posted a 3.52 ERA last season in the NL. After switching leagues, he now has a 5.90 ERA in AL. This means regression. Using ERA is a basic premise that many sabermetricians would scoff at, but hopefully it can be used to generalize results with a big enough sample size.
Since 2006, there were a total of 43 starters to switch leagues. Based on their before-and-after ERAs, each was classified under Regression, Improvement or Incomplete. Incomplete grades were given out if a pitcher was assigned to the minor leagues with his new club, relegated to the bullpen or suffered a career-ending injury. There were five Incompletes doled out, meaning 38 players were graded.
THE RESULTS
The perception is accurate: Pitchers from the National League struggle in their first year with new teams. Vice versa: Starters from the American League improve when they flop leagues.
Since 2006, 22 starting pitchers moved from the NL to the AL, two got Incompletes, eight improved and 12 regressed. Of the 20 graded starters, 60 percent regressed.
(It’s also important to note that 2006 was an outlier season where four of the six new American League pitchers improved. Miguel Bautista, Andy Pettitte, Ramon Ortiz and Steve Trachsel all lowered their ERAs with their new clubs, while only Tomo Ohka regressed, and John Thomson was Incomplete.)
There were, conveniently, almost the same number of starting pitchers over the eight-year window switching from the AL to the NL. Of the 21 that did, three got Incompletes, seven regressed and 11 improved. Therefore, 61% of graded players improved after making the league switch.
Perhaps the most interesting finding in the entire experiment was the elevated frequency of pitchers hopping to the National League. From 2009-2011, only three pitchers made the switch: Chien-Ming Wang (improved), Dustin Moseley (improved) and Erik Bedard (regressed). But between the last two offseasons, a dozen starters have made the switch with seven of the 12 improving. Most notable for Twins fans is Francisco Liriano, who turned a 5.40 ERA with the Twins and White Sox in 2012 into a 3.02 with the Pirates a year later.
In those same two offseasons – 2012 and 2013 – just five starting pitchers were brought from the NL to the AL. Guess which team signed three of them? You guessed it. Your very own Minnesota Twins.
Mike Pelfrey regressed to a 5.19 ERA from a 4.74 (I ignored the year Pelfrey missed before free agency due to Tommy John.) Kevin Correia actually improved by three-hundredths of a point, but that isn’t saying much when all he had to beat was a 4.21. As for Ricky Nolasco, he has the worst ERA in all of baseball, though he may have been pitching with an elbow injury.
As for Phil Hughes – a lifelong American League pitcher – the former Yankee has been fantastic, posting 10 wins before the All-Star Break.
The warnings are valid, as it turns out. Beware of the National League starting pitcher.
When will the Twins get the memo?
| Sam Ekstrom is a staff writer for Cold Omaha at 105 The Ticket. He has previously served as a play-by-play broadcaster in Iowa and South Dakota and has covered Minnesota sports since 2012. Follow him on Twitter @SamEkstrom for further insights |