Former Florida Gators receiver Antonio Callaway has a lot riding on his performance at this week's NFL scouting combine.Not so much on the field. It's more about what he does off of it, NFL Network analyst Mike Mayock said."He is very talented … and he's got a lot of off the field stuff that is going to affect his ultimate evaluation," Mayock said Monday in a teleconference with reporters. "That's why, quite frankly, what he does off the field at the combine is really more important. It's more about the meetings at night, the conversations he's going to have."Callaway, listed at 5-foot-11, 197 pounds at UF, was the first player in UF history to score a touchdown by rush, catch, pass, punt return and kickoff return in a career. He did that in only two seasons because the Gators suspended him for all of last season for his alleged role in a credit card fraud scandal.The Miami native also had a marijuana citation and admitted to being high on marijuana when UF investigated a sexual assault allegation against him. He was ultimately cleared of wrongdoing in that case.Mayock said Callaway's talent and off-the-field issues make him a likely third-day pick."People will recognize his talent," Mayock said. "They'll recognize his explosiveness and his ability to return the ball…I think a team has to get comfortable with who he is off the field."Other notable players Mayock mentioned Monday:He said Clemson receiver Deon Cain (Tampa Bay Tech) reminds him of Dolphins receiver Kenny Stills and "might be a little bit undervalued."Mayock liked Miami running back Mark Walton, who is a nice "change of pace" but missed most of last season with a knee injury.He called Penn State running back Saquon Barkley a "transformational back," like Leonard Fournette or Ezekiel Elliott. Barkley is a potential Bucs target at No. 7, if he lasts that long.He said Louisville quarterback Lamar Jackson is the "most electrifying player in this draft."Gators defensive lineman Taven Bryan is a borderline first-round pick, according to Mayock.