Notes: Hitter ratings account for the opposing starting pitcher's past history (three years' worth, as well as the past 21 days) and ballpark factors. "LH" and "RH" ratings account only for left- and right-handed batters, respectively. Weighted on-base average (wOBA) is the primary statistic used in the calculation. Ratings range from 1 to 10, with 10 representing the best possible matchup, statistically speaking, and 1 representing the worst. So, for example, a 10 is a must-start rating, whereas a 1 should be avoided (if possible); a 1-2 is poor, 3-4 is fair, 5-6 is average, 7-8 is very good and 9-10 is excellent.