Football rookies listen to docent Herb Garnes, right, as he shares the history of the face and head protection in pro football during a visit to the Pro Football Hall of Fame, Wednesday, June 24, 2015, in Canton, Ohio, as part of the NFL Rookie Symposium. (AP Photo/David Richard)

Cleveland Browns defensive lineman Danny Shelton takes a picture in the gallery during a visit to the Pro Football Hall of Fame, Wednesday, June 24, 2015, in Canton, Ohio, as part of the NFL Rookie Symposium. (AP Photo/David Richard)

Kansas City Chiefs wide receiver Chris Conley, left, signs an autograph for a student after football drills at the NFL Rookie Symposium in Berea, Ohio, Tuesday, June 23, 2015. (AP Photo/David Richard)

Cincinnati Bengals free safety Derron Smith, right, wears a helmet from 1969 while viewing an exhibit with Indianapolis Colts defensive end Henry Anderson during a visit to the Pro Football Hall of Fame, Wednesday, June 24, 2015, in Canton, Ohio, as part of the NFL Rookie Symposium. (AP Photo/David Richard)

Oakland Raiders linebacker Ben Heeney views the ball cap rack in the store during a visit to the Pro Football Hall of Fame, Wednesday, June 24, 2015, in Canton, Ohio, as part of the NFL Rookie Symposium. (AP Photo/David Richard)

Pro Football Hall of Fame Inductee Anthony Munoz, second from left, poses in front of his bronze bust with Cincinnati Bengals' Cedric Ogbuehi, left, Jake Fisher, second from right, and P.J. Dawson during a visit to the Pro Football Hall of Fame, Wednesday, June 24, 2015, in Canton, Ohio, as part of the NFL Rookie Symposium. (AP Photo/David Richard)

San Diego Chargers running back Melvin Gordon pretends to throw a replica football from the early 1900s during a visit to the Pro Football Hall of Fame, Wednesday, June 24, 2015, in Canton, Ohio, as part of the NFL Rookie Symposium. (AP Photo/David Richard)

Indianapolis Colts running back Josh Robinson reacts with students during a football passing drill at the NFL Rookie Symposium in Berea, Ohio, Tuesday, June 23, 2015. (AP Photo/David Richard)

Cleveland Browns defensive lineman Danny Shelton reacts during football blocking drills at the NFL Rookie Symposium in Berea, Ohio, Tuesday, June 23, 2015. (AP Photo/David Richard)

Pittsburgh Steelers defensive tackle Leterrius Walton, right, watches a student during a football passing drill at the NFL Rookie Symposium in Berea, Ohio, Tuesday, June 23, 2015. (AP Photo/David Richard)

Tennessee Titans quarterback Marcus Mariota speaks with the media while taking a break from football drills during the NFL Rookie Symposium in Berea, Ohio, Tuesday, June 23, 2015. (AP Photo/David Richard)

Tennessee Titans running back David Cobb, left, and Miami Dolphins guard Jamil Douglas compare hands sizes to former players during a visit to the Pro Football Hall of Fame, Wednesday, June 24, 2015, in Canton, Ohio, as part of the NFL Rookie Symposium. (AP Photo/David Richard)

Tennessee Titans linebacker Deiontrez Mount, right, races 9-year-old Alijah Gates, of Cleveland, during the NFL Rookie Symposium in Berea, Ohio, Tuesday, June 23, 2015. (AP Photo/David Richard)

Pro Football Hall of Fame president David Baker speaks to football rookies during their visit to the Pro Football Hall of Fame, Wednesday, June 24, 2015, in Canton, Ohio, as part of the NFL Rookie Symposium. (AP Photo/David Richard)

Jacksonville Jaguars wide receiver Neal Sterling, left, talks with a student during football drills at the NFL Rookie Symposium in Berea, Ohio, Tuesday, June 23, 2015. (AP Photo/David Richard)

Tennessee Titans quarterback Marcus Mariota interacts with students during football drills at the NFL Rookie Symposium in Berea, Ohio, Tuesday, June 23, 2015. (AP Photo/David Richard)

Nine-year-old Brandon Buttrick (left) of Cleveland, reacts with New York Jets defensive lineman Leonard Williams (center) and Baltimore Ravens tight end Maxx Williams during a running drill at the NFL Rookie Symposium in Berea, Ohio, Tuesday, June 23, 2015. (AP Photo/David Richard)

Tennessee Titans tackle Jeremiah Poutasi compares his arm size to former center Bern Brostek during a visit to the Pro Football Hall of Fame, Wednesday, June 24, 2015, in Canton, Ohio, as part of the NFL Rookie Symposium. (AP Photo/David Richard)

Oakland Raiders linebacker Ben Heeney poses in the bust gallery during a visit to the Pro Football Hall of Fame, Wednesday, June 24, 2015, in Canton, Ohio, as part of the NFL Rookie Symposium. (AP Photo/David Richard)

Tennessee Titans quarterback Marcus Mariota explains a football drill to students during the NFL Rookie Symposium in Berea, Ohio, Tuesday, June 23, 2015. (AP Photo/David Richard)

Tennessee Titans quarterback Marcus Mariota (center) speaks with the media while taking a break from football drills during the NFL Rookie Symposium in Berea, Ohio, Tuesday, June 23, 2015. (AP Photo/David Richard)

Cleveland Browns offensive lineman Cameron Erving takes a picture in the photo gallery during a visit to the Pro Football Hall of Fame, Wednesday, June 24, 2015, in Canton, Ohio, as part of the NFL Rookie Symposium. (AP Photo/David Richard)

Tennessee Titans quarterback Marcus Mariota takes a break from football drills during the NFL Rookie Symposium in Berea, Ohio, Tuesday, June 23, 2015. (AP Photo/David Richard)

Cincinnati Bengals linebacker P.J. Dawson shops in the store during a visit to the Pro Football Hall of Fame, Wednesday, June 24, 2015, in Canton, Ohio, as part of the NFL Rookie Symposium. (AP Photo/David Richard)

Tampa Bay Buccaneers quarterback Jameis Winston, left, and fullback Joey Iosefa, second from left, play a game with students during the NFL Rookies Symposium in Berea, Ohio, Friday, June 26, 2015. (AP Photo/David Richard)

Dallas Cowboys' Mark Nzeocha, right, makes a catch beside Damien Wilson during the NFL Rookies Symposium in Berea, Ohio, Friday, June 26, 2015. (AP Photo/David Richard)

Tampa Bay Buccaneers quarterback Jameis Winston, center, speaks with the media during the NFL Rookies Symposium in Berea, Ohio, Friday, June 26, 2015. (AP Photo/David Richard)

Arizona Cardinals' D.J. Humphries, center, reacts during a break at the NFL Rookies Symposium in Berea, Ohio, Friday, June 26, 2015. (AP Photo/David Richard)

Tampa Bay Buccaneers quarterback Jameis Winston, rear center, and fullback Joey Iosefa, back right, play a game with students during the NFL Rookies Symposium in Berea, Ohio, Friday, June 26, 2015. (AP Photo/David Richard)

A student participates in a running drill station with Minnesota Vikings' Stefan Diggs, left, and Edmond Robinson, right, during the NFL Rookies Symposium in Berea, Ohio, Friday, June 26, 2015. (AP Photo/David Richard)

Tampa Bays Buccaneers' Donovan Smith, center, stands in a huddle during the NFL Rookies Symposium in Berea, Ohio, Friday, June 26, 2015. (AP Photo/David Richard)

A student runs through a football blocking station with Chicago Bears' Hroniss Grasu, left, and Eddie Goldman, right, during the NFL Rookies Symposium in Berea, Ohio, Friday, June 26, 2015. (AP Photo/David Richard)

Tampa Bay Buccaneers quarterback Jameis Winston, right, throws a football during a passing drill at the NFL Rookies Symposium in Berea, Ohio, Friday, June 26, 2015. (AP Photo/David Richard)