Edwin Jackson has had a pretty good career to date, with a 14-win season and a 3.62 ERA campaign on his resume by age 27. He's made at least 31 starts in each of the last four seasons and topped 209 innings in the last two, so his ability to take the ball every fifth day alone will get him paid as a free agent. If this is all Jackson will ever be, that's not bad. But seven years ago, when Jackson was considered the fourth best prospect in the game by Baseball America, he was expected to become much more than a solid #4 starter.
Jackson reached the Majors as a 20-year-old with the Dodgers, outdueling Randy Johnson in his debut. Since then he's been traded four times. Jackson's career numbers are middling: a 4.62 ERA, 6.7 K/9, 3.9 BB/9, 1.1 HR/9, and more hits allowed than innings pitched. When he was traded from the Diamondbacks to the White Sox for Dan Hudson and David Holmberg on July 30th last year, he looked like the same old Jackson: mid-90s fastball, flashes of brilliance (including an eight-walk no-hitter in June), and disappointing statistics.
Something changed with the White Sox. It appears that pitching coach Don Cooper helped Jackson make a few adjustments, as he was brilliant in 11 starts for Chicago: a 3.24 ERA, 9.2 K/9, 2.2 BB/9, 1.0 HR/9 and 47.2% groundball rate in 75 innings. Note that Jackson's groundball rate leap actually began with the Diamondbacks.
The Chicago sample size is small but tantalizing. Jackson even had a three-start stretch in August where he struck out 32 against just six walks in 23 2/3 innings. If Jackson's superb strikeout and walk rates hold up over a full season, he could become the best available free agent starter aside from C.C. Sabathia. He'll reach the market as a 28-year-old with Scott Boras at his side, which could make three years and $30MM required just to begin the discussion. Boras will just have to avoid Oliver Perez comparisons.