"He'll work out today," Gibson said. "He'll be out there, take ground balls, and he'll swing. He'll do everything today except play in the game."
Gregorius was put on the DL with a mild concussion on April 28, retroactive to April 27. He was struck in the head by a 93 MPH fastball from Rockies pitcher Josh Outman on April 26.
"Everything that is required and mandated by the team, they follow. You can rest assured our training staff is as good as anybody out there," said Gibson when asked about the timeline. "If he's doing what he's doing, obviously he's passed everything he needs to pass.
"As far as I know, today is the first day he's cleared to do all the activities on the field besides play."
The 23-year-old initially suffered a contusion to his right temple. At the time of his injury, Gregorius was hitting .407 in 30 plate appearances with the D-backs.
Aaron Hill not close
Gibson also gave an injury update on veteran infielder Aaron Hill. He's progressing but won't be coming back any time soon.
"This week he saw the doctor and they left him in a splint. Next up for him, I think in another week he'll go back. They did some strength tests and stuff," said Gibson Tuesday. "Next he'll start doing more exercises and stuff like that. I think they look to see how much the bone is regenerating. He's not there yet."
Hill was put on the 15-day DL with a broken hand on April 15. He suffered the injury when he was hit by a pitch on April 9 against Pittsburgh.