I've written about this once before (I won't link to it, because why?), but only in passing, and it deserves more than that.
Entering the 1966 season, the newly-moved-to-Atlanta Braves' Tony Cloninger was a promising young pitcher. He was 26. He'd been in the league for five years, and had seen a steady increase in just about everything -- innings, wins, strikeouts and strikeout rate, ERA+ (with the corresponding drop in ERA), etc. In '65, Cloninger finished in the top ten in wins, innings, strikeouts, starts, and homers per nine (while also leading the league in walks, and posting just a 107 ERA+). He wasn't a superstar, yet, but he seemed to be heading in the right direction.
One thing it didn't look like he'd ever become, though, was a hitter. Cloninger was a pretty typical pitcher on that front; he'd finally hit his first home run in 1965, and in his five-year career, he was a .174/.179/.211 hitter in 329 plate appearances. That's a little bit better than the pitcher's norm -- NL pitchers hit .138/.170/.175 as a group in '65 -- but certainly not enough better to get excited about.
Then, 1966 happened.
