The Big Unit

Randy Johnson, the Big Unit, was elected yesterday to baseball's Hall of Fame in his first year of eligibility.  Joining him were Pedro Martinez (see Pedro Fans 17), John Smoltz and Craig Biggio.  The election of Randy and Pedro was a given this year.  At his peak, Pedro Martinez was as good or better than any pitcher in baseball history, but it was a short career overall.  Randy Johnson (who has started a second career as a photographer since retiring from baseball) is in the discussion when talking about the best left-handed pitchers ever.
(from oregon live.com)

So where does the Big Unit stand on the list of the best left-handed hurlers?

First, the man himself.  At 6'10" with scraggly hair, wiry body and just a mean look Johnson was one of the most intimidating pitchers of his era.  Particularly if you were a left-handed batter.  With his long arms and sidearm motion if you were left-handed it looked like he was throwing a rocket right at your head, or behind it.

This is from the 1993 All-Star game at Camden Yards in Baltimore, which THC was fortunate to attend.  Randy is facing John Kruk, a pretty good, but left-handed, hitter.  Watch what happens.
It got to the point where left-handers rarely faced the Big Unit.  This is his 20-strikeout game in 2001 against the Cincinnati Reds; note that there is only one left-hander in the lineup against him.
Johnson pitched from 1988 to 2009 with a record of 303 wins and 166 losses along with striking out 4,875 batters, second only to Nolan Ryan, including a record four consecutive seasons of 300+ strikeouts (averaging 354).  The man generally considered the greatest lefty is Lefty Grove (1925-41) with 300 wins and 141 losses.

Two other names sometimes come up in the discussion.  The first is Sandy Koufax (see Dazzy Koufax and Gibson Koufax Marichal Mashup).   Koufax was a great, great pitcher but both his peak (5 seasons) and his career (11 seasons) were short.  He also pitched in a more friendly pitching era than either Grove or Johnson.  The other is Warren Spahn who won 363 games over a very long career, including being a 20-game winner thirteen times and whom we'll discuss further below.

The two metrics THC most relies on in evaluating pitchers are ERA+, which compares them to their league and normalizes for ballpark factors, and WAR, Wins Above Replacement.

Lefty Grove's fourteen season peak was from 1926 through 1939 within which he had one awful season (1934) pitching with an injured elbow before being disabled.  During that period his ERA+ averaged 148 (100 is league average) and his average WAR was 7.8 (a WAR of 8.0 is generally considered a season worthy of MVP consideration).  He also had to reinvent himself as a pitcher after the 1934 injury.

Randy Johnson had a twelve year peak from 1993 through 2004 (though he also had five effective years before and after the peak compared to two for Grove) within which he had two injury-shortened years.  In those seasons his average ERA+ was 136 with an average WAR of 7.1.
(Ouch!)

Warren Spahn had the longest peak (1947-1963) with an average ERA+ of 126 but had only two seasons when his ERA+ exceeded Grove or Johnson's average for their peak periods and his average WAR was 5.4.  As an example of his remarkable consistency Spahn had ten seasons of ERA+ within the narrow range of 119 to 125. Though never as dominating as Grove or Johnson he knew how to get batters out, declaring "a pitcher only needs two pitches, the one they're looking for and the one you throw them".

My ranking:

1.  Lefty Grove
2.  Randy Johnson
3.  Warren Spahn
4.  Sandy Koufax
5.  Steve Carlton

Three other interesting tidbits that popped up in researching this piece:

From June 25 through July 15, 1999 Randy Johnson started five games for the Arizona Diamondbacks, completing three.  He threw 40 innings, giving up only 25 hits and 12 walks, striking out 62 with an ERA of 1.25.  He had four losses and a no-decision!  The game scores were 0-1, 0-2, 0-1, 0-2 and 2-3 (a game he left after 8 innings with a shutout). He won his next outing by throwing a shutout and then lost his next start in a complete game 1-2 loss.

1999 also shows the problems with relying on won-loss records to judge pitching effectiveness.   Through June 20, Johnson's record was 9-3 with an ERA of 3.36.  He posted an ERA of 1.85 over the remainder of the season but his record declined to 8-6.

Looking at the Big Unit's performance over the years at Baseball-Reference illuminates a striking change in pitching over the last decade; the increasing emphasis on pitch count resulting in fewer complete games.  Today, pitchers rarely exceed 100-110 pitches in a start and almost never exceed 120.  Johnson's pitching log shows him routinely throwing more than 120 pitches and exceeding 140 several times a year.  While looking at the data, THC got curious and looked at Nolan Ryan (see The Ryan Express).  Unfortunately we only have pitch counts starting in the late 1980s but the limited information on Ryan is startling.  In 1989, at the age of 42, Ryan threw 147, 146, 150 and 164 pitches in consecutive starts!