One of the most repeated bits of managerial wisdom by bloggers, play-by-play crews and fans in baseball has been common knowledge for a very long time: never walk the lead off batter, because it will come back to bite you.

Late last night (okay, really early this morning), a discussion on Twitter between my co-writer at “You Can’t Predict Baseball” @jordansmed and @richardiurilli on the subject emerged; most notably, they were looking for the actual number as to how many lead off walks actually do come around to score.

So, of course, I thought it’d be a good idea to go try.

Here’s the thing, though: Baseball Reference will tell you how many times a team walked to lead off an inning, and you can use the play index to find a list charting all of a team’s walks, including the date, game, inning, bases/outs situation, etc…but if you want to find out if that actual walk came around the bases to score, you have to go to the game log to look it up. It’s doable, but tedious.

Of course, I’m, uh, stupid inquisitive enough to do it anyway.

So. Here’s the criteria I used:

1) I looked at ONLY Yankee walks in 2010. I did not count walks by an opponent that came around to score.

2) Walks had to occur with no one on base and no one out in the inning (thus, a lead off walk). ONLY walks were counted–no HBP, no hits, no errors; just walks.

CAVEAT: I included ONLY walks that truly led off an inning, not walks that occurred with no one on and no one out after a lead off home run.

3) The runner that walked had to be the runner that scored. For example, if Teixeira walks and scores on a Canó double, that counts. If Teixeira walks, Canó grounds into a force at second and then Canó scores on a Granderslam, I didn’t count it because it wasn’t Teixeira that scored.

4) ONLY the batter that walked is counted; any subsequent runs are not counted.

5) All box scores and play-by-play can be found on Baseball Reference (as well as a host of other sites, but I used baseball reference). The Play Index’s chart of 2010 Yankee walks can be found here. You may need a subscription to access the entire thing, I’m not sure.

So, the Yankees, so far in 2010 have had a total of 95 walks that led off an inning.

Of those 95, 41–or 43%–came around to score, and this doesn’t include leadoff HBPs or innings in which the lead off walk was forced at second, but the next runner came around to score.

Forty-three percent is, of course, much less than the oft-cited 60%, but I would include two caveats:

1) It’s still a very significant number, and
2) These are just the Yankee numbers for 2010–across a whole host of seasons or different teams, the number might be different. That said, the 2010 Yankees have one of the best offenses in baseball (with 679 runs, they’ve scored more than any other team in the league), so take that as you will.

If you’d like to know which leadoff walks did, in fact, come around to score, I jotted them down below:

You can find individual game logs here/

So yeah, don’t walk the lead off hitter.