Hill, who has been sidelined for nearly a month with post-concussion symptoms, was instructed this past weekend to stay away from the team for a two-week period. After that time has passed, the Jays will re-evaluate Hill's situation.
"We're in uncharted waters," Ricciardi said. "I think we'd be crazy to say he'd be back in one week, two weeks, three weeks. I think it's one of these things that has to run its course, but we don't know. He may come back in 10 days and say, 'I feel great.'"
Ricciardi said Toronto's medical staff examined Hill on Tuesday and relayed a good report.
"The trainers told me he felt a little better today," Ricciardi said. "But that's going to be a long haul, I think."
The 26-year-old Hill was struck on the side of the head by shortstop David Eckstein during a play in the seventh inning against Oakland on May 29. This past weekend in Pittsburgh, the second baseman met with a concussion specialist at the University of Pittsburgh Medical Center.
"The explanation I got," Ricciardi said, "they said, because it was a blow he wasn't ready for, it's kind of like a sucker punch almost. He didn't have a chance to tighten his body up, where your body absorbs the hit.
"In his case, he just kind of got smoked without seeing it coming. It's just unfortunate."
Jordan Bastian is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.