The Tigers expect Martinez to be strong enough to begin running this fall, but that won't happen until November, since there's no rush.
Martinez had no setback, Rand said. He just didn't progress quickly enough.
"When we did the strength assessment at the end of July, [based on] where he was at that point, we felt that we would probably [be where we are] at this point," Rand said. "We gave it a couple of more weeks to kind of push and see where it put him.
"The bottom line is, we needed so much time as far as a running progression is concerned, as far as getting in baseball work, skill work, getting him ready to come back, and we're not going to have the opportunity to do that."
Martinez is pretty much where he was in the spring, after a fall during offseason agility drills blew out his left knee. He underwent the microfracture surgery on a torn meniscus at the end of January and was scheduled for reconstructive surgery on his torn anterior cruciate ligament in April.
Martinez's injury prompted the Tigers to sign then-free agent Prince Fielder to a nine-year, $214 million contract.
After a followup exam, however, Dr. Richard Steadman -- who performed the January surgery -- determined that the ACL didn't require reconstruction. Instead, Martinez underwent a more minor procedure to help the healing process.
That raised hopes for both Martinez and the Tigers. But a possible return would be a chance, not a certainty, and not one the Tigers would risk his long-term health to make.
"The biggest thing for me is looking at the bigger picture," Rand said. "And the bigger picture is, we've got this guy signed for four years. This is his second year, and we've got years three and four to worry about. We want the guy ready to go and healthy."