While it isn't a large sample size, we can take a quick look at some trends over the first 10 games or two starts per starter.
Scott Kazmir is back. Or at least it looks like Kaz is back. He is throwing the slider 23.1% of the time which is the highest since 2006. With slider now back, Kaz has become more of a groundball pitcher. After experiencing a huge jump to 48.9% flyballs (sans slider) in 2008, Kaz is now back to normal with 40.5% groundballs and 37.8% flyballs. Also he is throwing more first pitch strikes than ever which have led to two effectively efficient outings.
James Shields is getting better. After a disaster in the opener, Shields was much better in his seven innings of shutout baseball in Baltimore. Shields still doesn't have his good control yet as you can see with his poor 1.25 K/BB. While the walks were down in the second start, the strikeouts haven't been there yet. He has just five on the season and is going to need to get that up to have the same success of past seasons. One explanation could be an increase in breaking balls. Shields is throwing more sliders than ever and has increased his curveball usage. It's helping in the ground ball area and could help in the K/BB and K/9 once he gets a better feel for them.
Matt Garza. THIS IS GARZA or at least what I expected from Garza; lots of strikeouts. In fact one per inning (14 K in 14 IP) this makes for a nice round 9.0 K/9. His walks are slightly up, but the increase in K's makes up for the increase in free passes. Usage wise, he's actually throwing less fastballs with more sliders and a lot more curveballs. I pegged Garza as a breakout candidate in 2009 and so far so good.
Andy Sonnanstine is a lot like James Shields. They need control more than their stuff and like Shields, Sonny improved from start to start. He has almost gone exclusively to a cut fastball and is throwing more curves and less sliders than normal. This has made him more of a flyball pitcher which is not really a good thing for him. As the control comes back, he will need to have command of his pitches low in the zone to induce more grounders. As for the changeup we all heard about during the spring? Sonny has definitely used it more; 0.6% more to be correct. Big change.
Not going to get much into Jeff Niemann as I broke his stuff down earlier this morning, but Niemann has been a normal fifth starter. As for the future, a 95 mph heater with a good curve out of the bullpen may seriously be the answer for Niemann long term and the Rays early season bullpen woes.