Ryan Dempster (2-4, 3.75)
Dempster is in his 16th major league season and he hasn't shown any signs of slowing down. In fact, his strikeout rate is currently the best it's ever been in his career (11.44 K/9). While he's been doing a great job of missing bats and limiting hits (.203 batting average allowed), he's struggled with the long ball as he's already allowed 9 home runs in 48 innings this year, though a good chunk of those came in his last start against Toronto when he gave up 3 homers and 6 runs in 5 innings. Dempster actually faced the Twins back on May 7th, and he took the loss in allowing 4 runs in 7 innings.
There are three main pitches in Dempster's repertoire, and that is a fastball, slider, and splitter. The slider and splitter are his most effective pitches, and he trusts his slider so much that he throws it almost as often as his fastball. Also, Dempster does an odd glove shake while he pitches, which is apparently done so hitters don't see him adjust his pitch grip prior to delivering the ball.
Scott Diamond (3-3, 4.08)
Scott Diamond is selfish. Why? Well, he has received a decision in every one of his 6 starts this year. However, he hasn't been striking anyone out (3.82 K/9) so in Crash Davis' eyes, he's not really that selfish. Still, Diamond has countered the excessive contact (.296 batting average allowed) by using his excellent control (1.53 BB/9) to keep his WHIP down to a respectable 1.30. Diamond actually opposed Dempster on May 7th in Boston, and he got the win by keeping the Red Sox scoreless through 7 innings.
Diamond also throws only three pitches, and he generates a ton of ground balls despite not actually throwing a sinking fastball. Instead, he relies on creating a good downward plane (curse you Bert Blyleven!) and aiming his 4-seam fastball at the bottom half of the zone. It also helps that he can sometimes get some cutting action on his 4-seamer. He will mix in a curveball and change-up as well, and his curveball is slightly above average while the change-up is solidly below-average, according to FanGraphs' pitch values.