But if Ervin Santana continues to struggle, and Dan Haren's disabled-list stint doesn't heal his stiff lower back, can that change?
"That remains to be seen," Angels general manager Jerry Dipoto said Friday, a day two of his scouts were in Miller Park watching Greinke pitch. "It's not like we're looking at this as a volatile time [for the rotation]. Ervin's 100-percent healthy, we're just looking to get him back on track, and Danny's making terrific progress. And I don't necessarily think we're going to be having discussions like this a month from now. As I told you before, I think the best moves that we can make are getting Ervin back on track and getting Danny healthy."
The prognosis, at least in these early stages, looks positive for Haren, who had an encouraging bullpen session in Anaheim on Thursday, is slated for another one at Inland Empire, Calif., on Saturday, and looks to be on track to return from the disabled list at or around the time he's eligible -- this coming Thursday.
The Angels still have to decide who starts in Haren's place on Tuesday -- a decision that may come down to Brad Mills or Garrett Richards -- but they're hoping they only have to fill his spot once more.
And they seem confident that a couple of weeks off will make all the difference for Haren, who has posted a 4.86 ERA while giving up 16 homers in 17 starts.
"He feels a lot better," Angels pitching coach Mike Butcher said. "His stuff looked really good yesterday -- I mean really good; getting through the baseball like he can, delivery looked better. He was really tight [in his back] to where it really affected his delivery; he wasn't able to get through the ball like he can. So, I think we'll see a different guy when he comes back. He'll be a lot more healthy."
Santana doesn't have the benefit of using injury as an excuse. His arm is totally healthy and, by all accounts, his stuff and velocity are fine. His problem is location. More specifically, as Butcher noted, it's not locating well enough early in counts, causing him to pitch from behind too frequently.
That could be a byproduct of lacking confidence, perhaps stemming from getting hit around early in the year.
"When a pitcher goes out there, and you give up home runs or what have you, you might tend to lose a little confidence," Butcher said of Santana, who has posted a 5.75 ERA and has given up 20 homers in his 17 starts. "And that's why guys start nibbling a little bit. I think once he starts being the aggressor, starts attacking the strike zone, I think we're going to see better results out of Ervin."