The fracture was caused when Greinke lowered his left shoulder to take the blow of the Padres' Carlos Quentin, who charged the mound after being hit by a Greinke pitch for the third time in their careers. The force of the blow on the shoulder created a significant fracture of Greinke's collarbone closer to the shoulder than the sternum.
The fracture was repaired with a metal plate and screws, and the original prognosis was a two-month recovery. Greinke is ahead of that, but running and fielding also pose potential risks to the healing bone.
Greinke described his pitching arm strength as "pretty good" after a third bullpen session Tuesday. He's taken a couple of "dry swings" with a bat, "but I didn't try to hit an imaginary home run." He said catching throws is "pretty easy."
"I feel more than you would with a normal arm, but not anything major," Greinke said.
Greinke's normal bullpen sessions are brief (25 pitches) and more intense. He estimated he made 60 throws Saturday and Tuesday "just building endurance" and "no pitches are a problem." Manager Don Mattingly said Greinke's bullpen pitches have already been clocked as fast as 90 mph.
Greinke opposes the suggestion that baseball adopt a brawl policy similar to the NBA or hockey, with immediate consequences for a third party entering a fight.
"It think it's part of the game, or has been forever and any rule changes could backfire in different ways," Greinke said.
"What do you do, get in a fight and go one-on-one until some person dies? The umpire doesn't do much. It's not like a brawl and they're coming off the bench bringing weapons. Most people coming out are trying to calm things down, not encourage it."
Ken Gurnick is a reporter for MLB.com. Austin Laymance is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.