Q: Why is Mike Mussina Such A Good Bet This Season?

A: Pitcher Orientation

Mike Mussina's record improved to 5-1 on Friday and it got me to thinking about how the dude's ERA has gone down more than 2 runs per game from last season. Mike Mussina has been a very solid part of the Yankees pitching staff since he came to the Yankees in 2001 but this year is turning out to be his best season so far.

He was injured in 2004 and recovering from some aches in 2005 so we knew he would bounce back this year but to start off as good as he has is impressive.

Mussina's success could not come at a better time. Randy Johnson is 5-2 but has a bloated 5.00 ERA. Shawn Chacon, Chien-Ming Wang, Jaret Wright are not putting in the innings necessary of starting pitchers. Then Mr. 10-0 last year Aaron Small is still diddling around in the bullpen with a loss already on his record.

Without Mussina's 5-1 record, these Yankees would be the worthless 500-ish ball club we expected them to be. Mired in mediocrity, they would be sitting in third place of the AL West. I admit that taking away the best pitcher of most teams results in a lousy team but Mussina is not supposed to be the best pitcher on this team!

There is statistical evidence suggesting that Mussina will continue his string of excellence this season but it is all because of Randy Johnson. You can say what you want about Johnson but realize that his mere presence in the starting rotation gives Mussina additional victories.

Imagine you are a batter in a series facing the flame throwing lefty Randy Johnson and had to adjust to his velocity and location the whole game and then were expected to face Mike Mussina the very next day. With Mike Mussina being a righty, it becomes tough for you as a hitter to become comfortable in the batter's box. You will be off balance.

Here are some statistical results over the past 7 full seasons for you to consider.

Win Percentages Against Right Handed Pitchers:

• Leage Wide: 50.4%
• If faced a lefty the previous game: 49.7%
• If faced a righty the previous game: 50.7%

As you can see, there is a significant 1.0% blind improvement Mussina is getting just by going after a lefty like Randy Johnson. This improvement is league-wide and even includes horrible right handed pitchers and horrible teams.
But what we noticed was that it mattered more how well the lefty pitcher was versus how well the righty pitcher following him. So we constrained our sample to teams coming off a poor offensive performance usually at the hands of a dominant pitcher.

Win Percentages Against Right Handed Pitchers After Scoring Less Than 2 Runs:

• Leage Wide: 49.3%
• If faced a lefty the previous game: 47.3%
• If faced a righty the previous game: 50.0%

The disparity now grows to 2.7%, an increase of about 3 times.

We see Randy Johnson's mere presence in front of Mussina is helping despite not having a great season up to this point. Once Randy Johnson gets better, so will the Moose and we will continue to look at him in good betting spots.

Check out our other pitcher orientation articles for more analysis on this issue.

1. How Pitcher Orientation Should Impact Baseball Betting Odds
2. Pitcher Orientation in Bounce Back Games
3. Pitcher Orientation Matters Little in Division Rivalry Games