You can banter with Kershaw, but not Greinke
From ESPN's profile of Clayton Kershaw
"Usually, it evolves into all of us ganging up on Kersh and giving him a hard time about something," Ellis says. "He's an easy target because he doesn't fire back. You can't pick on Zack Greinke, because Zack will bury you. If Kersh makes fun of me, I know it's maybe 70 percent true and 30 percent joke. If Zack makes fun of me, it's 100 percent true and I may have to go look in the mirror for a while and think, I might have to make some changes.