Injury concerns have been difficult to shake for these three gifted prospects and represent the main reason one, if not all, could be available at the Ravens' 25th overall pick.
A player's health is as scrutinized as his character. Limbs are twisted and yanked. Any crack in a bone — or any crack in an injured player's Pro Day performance — instantly causes concern.
Perhaps the biggest fear on draft day is forking over $8 million (which is what the 25th overall pick is likely to receive) to damaged goods.
"These are million-dollar decisions," said Eric DeCosta, the Ravens' director of player personnel. "When that much money is on the line, you have to exhaust every resource."
The Ravens' medical process begins when their scouts talk to the college trainers. The next step is for the team to research the injury on a Web site that is accessible only to college and NFL trainers.
The Ravens bring their entire medical staff (which includes Bill Tessendorf, the longest-tenured trainer in the NFL) to the scouting combine in Indianapolis to check out players. If there are any red flags, the Ravens have the opportunity to bring in 30 players to their facility for a second examination.
Every player says he's 100percent healthy. Every team has 100 doubts.
From the combine in February through the Pro Days in March and April, the Ravens put a player's 40-yard time and his execution in position drills under the microscope to find out where he is, medically.
"It's essentially a pass or fail," DeCosta said.
The Ravens have built a reputation — as well as a championship team — by taking risks, albeit calculated ones.
The team used the fourth overall pick on linebacker Peter Boulware in 1997, when there was talk that he had an abnormal posterior cruciate ligament, a condition that dated to high school. Three years later, the Ravens invested the fifth overall pick in running back Jamal Lewis despite concerns stemming from major knee surgery late in his college career.
Boulware and Lewis blossomed into Pro Bowl players who were instrumental in the Ravens' Super Bowl triumph in January 2001.
"We've had some guys who were taken off other people's boards, medically," Ravens general manager Ozzie Newsome said. "But our staff decided that the guy should remain."
Gresham (knee), Thomas (foot) and Gronkowski (back) have different issues, but they understand the hurdles of proving themselves healthy.
In fact, there was speculation that Gresham wasn't available for his scheduled interviews at the combine because so many team doctors needed to examine the top-rated tight end in the draft.
"People don't miss those anymore," Cleveland Browns president Mike Holmgren said. "You check, then you have a recheck, then another recheck."
When healthy, Gresham is one of the most dynamic pass catchers in the draft, drawing comparisons to Kellen WinslowSr. But the Oklahoma prospect missed the entire 2009 season after undergoing knee surgery to repair cartilage in September, his second knee operation in five seasons.
"I've been yanked and tugged on and not one doctor said anything bad about it," Gresham said at the combine. "They said the knee's great and I'm good to go. I haven't got any problem with it at all. It's back to 100 percent."
While Gresham had an entire college football season to recover, Thomas didn't have that luxury. The Georgia Tech wide receiver broke a bone in his left foot Feb. 16, when he was running a cone drill to prepare for the combine.
The physical pain was compounded by the devastation that he couldn't work out at the biggest rookie event of the offseason.
"Once I did it, I felt real bad," Thomas said. "I started crying because I wanted to participate in stuff like this. It just hurt my heart."
Thomas needs to show teams that he can run routes because he comes from a run-oriented offense in college. Back jogging again, he is hoping to be ready for his late Pro Day today, which comes four days before the draft.
"There's a lot more work to be done on Demaryius across the league," DeCosta said. "That's going to be the challenge between now and April 22 — to do as much work on Demaryius as we can."
Perhaps the most difficult medical case is Gronkowski, the Arizona tight end considered the Ravens' dark-horse pick.
Gronkowski missed the 2009 season after back surgery to shave off a disk that was sticking out and onto his spinal cord. Needing six months to recover, he didn't participate at the combine.
NFLDraftScout.com recently reported that an NFL scout had confirmed that Gronkowski has been "red-flagged" by teams because of stenosis, a narrowing of the spine that can cause numbness and leave a person prone to paralysis.
His agent denied the report.
"Every team I have talked to says there are no concerns about his back," agent Drew Rosenhaus said. "He passed his physical at the combine. There are no red flags on him. He is ready to go. The back is not a factor. There's no issue."
Gronkowski boosted his draft status with an impressive Pro Day. He ran the 40-yard dash in 4.65 seconds and had only two drops in pass-catching drills.
Now, once the players are done with the drills and the medical tests, the Ravens must go to work. Ultimately, the decision boils down to this: Do these players pass or do they fail?
"Ozzie has made a living drafting players with injuries," one insider told Sporting News. "If Demaryius Thomas or Rob Gronkowski are sitting there, they may not get past Baltimore."