High-velocity low-command relievers are available dime a dozen in baseball. Producing radar gun readings that are alluring and tantalizing while never having a clue as to the final destination of the pitch is how most of these flamethrowers burn out. Occasionally though, one clicks and sets the league ablaze. Grant Balfour clicked last season.
Balfour finished with a swinging strike percentage just behind Joakim Soria and Kyle Farnsworth - Kyle Farnsworth is proof that getting swinging strikes does not always correlate to success - but I wanted to answer the question: does Balfour get more strikeouts (and swinging strikes) in higher leverage situations?
Short answer: no.
Here's a look at his splits:
| Leverage | PA | K% | BB% |
| High | 69 | 38 | 10.1 |
| Medium | 55 | 40 | 7.3 |
| Low | 100 | 34 | 13 |
And a graph:
There's not much of a correlation here.
Balfour's strikeout rates were at their best in "medium leverage" situations (when leverage is below 1.5 an above 0.7) as opposed to high (1.5+) and low (sub-0.7). That's great, considering Balfour's average pLI was around 1.3, meaning his best work came in the situations that Maddon used him the most in. Funny how that works out.
One trivial note, you see that ~4 leverage, ~60% swinging strike data point? Well, do you remember that game in Oakland where Balfour entered with a man on second and had to face Frank Thomas and Jack Cust? That's also the game where the Rays snapped Brad Ziegler's scoreless streak. I find it amusing that Balfour's stuff and the opposing batters were such a perfect match, leading to excellent results, and yet he still gets tagged with a blown save.
Also, here's an example of a Balfour induced swinging strike.
