Diamondbacks' Zack Greinke: Could begin rehab assignment Friday

Greinke (oblique) will throw an up-and-down bullpen session Tuesday, then could go out on a rehab assignment Friday, Fox Sports Arizona's Jody Jackson reports.

Analysis:

If Tuesday's throwing session goes well Greinke will either throw a simulated game or go out on a rehab assignment Friday. It is not clear whether Greinke will be able to return after one rehab game or if he will require several, but an early-August return appears to be within reach.