I think the closer position more than any other demonstrates the fascinating juxtaposition between predictive stats, statistical results, and the eye test. Great points by most everyone on this blog. Fact of the matter is that Perkins has worn down for 2 years straight under a normal work load. His velocity and K% was down all year despite getting great results for the first half of the season. Is the second half luck catching up with him? A change in his approach or hitter awareness? Lack of confidence after a shaky All-Star Game? His pitch tracking, shown somewhere in this blog awhile back, showed his slider was starting to elevate. Whether this is soreness, fatigue, or nerves, I have no idea. Personally, I think he was making up for his decline with fantastic location this spring. As the season wore on, his location started to go. I don't think we can expect his velo to come up dramatically, and his slider is flattening out. He can still be elite if he can peg his spots, but that's still a pretty big if. It did seem like his confidence took a hit, especially after A-Rod and the Yanks got him. He seems to take blown saves harder than many other elite closers. His mental toughness appears strong, but not unshakeable. Regarding closers in general, I think a good one gives you a strong psychological advantage. It helps define roles for other arms, and it causes the opposing team to press even more when trailing late. We can argue about predicting success based on non-metric based factors, but I enjoy looking at them because they make the game more interesting to follow for me. It even makes statistical analysis more interesting for me. Trying to figure out why someone is outperforming or under-performing their metrics is one of the most enjoyable parts of following Twinsdaily. Cue Glen Perkins, and Trevor May, our future closer whose firey nature, use of adrenaline, and success since moving to the pen make him a natural fit.