How deep is starting pitching in baseball?

A recent article in the Chicago Tribune suggested that the Chicago Cubs trade their young stud starter, Carlos Zambrano, for superstar shortstop Miguel Tejada.  Using Bill James' Win Shares we can look at the depth of starting pitchers in baseball and do a comparison to shortstops.  Let's start with shortstops.  Here are the top five shortstops in Win Shares in 2005.

Clearly, Tejada is one of the best.  Plus he's done this for years, with Win Share seasons of 28, 25, 32, 25, 23 and 20 going backward prior to this past season.

But how deep is the shortstop position?  Fifteen Win Shares in a season is a reasonably good season for any player. Given that there are 30 teams in baseball, let's look at the top 30 shortstops overall.   How many of them had 15 or more Win Shares in 2005?  Answer: 15 -- exactly half.

Now, let's take a look at the depth of starting pitchers.  Here are the top fifteen starting pitchers last year:

Each team needs five starters.  Using 30 teams again let's look at the top 150 starting pitchers.  How many of them had 15 or more Win Shares in 2005?  Answer:  24 -- only 16%.

Clearly, shortstop is a much deeper position than starting pitching.

Here's another angle.  How many teams had more than one pitcher with 15 or more Win Shares?

No other team had more than one.

The most successful teams are those that had the greatest depth at starting pitcher.

Most Cub fans would probably say that the Cubs need a shortstop.  However, let me also provide this to chew on.  Neifi Perez had 12 Win Shares for the Cubs last year.  That was slightly below average, but the former Gold-Glover anchors the infield with excellent defense.  But more importantly, the Cubs have one of the best shortstop prospects in all of baseball, Ronny Cedeno, waiting in the wings.  He may be ready this year.  They'll do fine starting with Perez and switching to Cedeno when he's ready.

If you're a Cubs fan, hope that this trade idea goes to the circular file under the desk of Jim Hendry.