Guess the Prospect!

I was a first round draft pick out of high school west of the Mississippi river. I pitched very well in my first pro exposure in rookie ball and full-season ball. In my first full season, I won more than 10 games at the A-ball level but had mediocre peripheral ratios. I had very good stuff but my control needed work.

In my second full season at age 20, I did much better, lowering my ERA significantly and improving my component marks. In my third pro season I reached Double-A and was dominant at times, with further improvement in my component ratios as I was gaining command of my stuff. I reached the majors in my fourth season at age 22, pitched well in relief. In my fifth season at age 23 I had a very strong season as a swingman in the majors. I was a full-time starter at age 24 and won a lot of games that year, but my ERA rose and I had command problems.

The following year I was hit very hard, hurt my arm, and got traded. Although I ended up recovering enough to be a rotation starter for the next several years, I lost most of my fastball and had to get by on breaking stuff and moxie. I'm still on a major league roster.

Who am I?