On Friday, Ravens GM Ozzie Newsome told reporters that the team had no prior indication that health was an issue for Grant.
"It's not a football decision. It's a medical decision that I had no control over," Newsome said.
Grant hasn't missed a game in his four-year career.
The GM added he believes the Ravens' team doctors are being fair in their assessment of Grant's medical condition.
"I trust those guys," he said.
Grant's agent, Rocky Arceneaux, would disagree. Arceneaux told ESPN's Adam Schefter that the wide receiver has been working out, and running routes. He also said his ankle was cleared after a second opinion from Dr. Robert Anderson.
The agent also said Grant is flying to meet with the Indianapolis Colts, NFL Network Insider Ian Rapoport reports. If he passes a physical, Grant could sign a new deal, but the circumstance means it will likely be for a lot less than he would have received from Baltimore.