Question: Which Ohio State Buckeyes football player is known for challenging the NFL's draft eligibility rules requiring a player to be three years removed from high school?

Context articles: Bill Doolittle
2002 Ohio State Buckeyes football team
Ohio State Buckeyes football statistical leaders
2012 Ohio State Buckeyes football team
Aurealius Thomas
2003 Ohio State Buckeyes football team
John B. Eckstorm
Boyd Cherry
Craig Krenzel
Maurice Clarett

Francis William "Bill" Doolittle (August 10, 1923 – April 10, 2014) was an American football player and coach.
 Doolittle attended high school in Mansfield, Ohio where he was selected as an all-state quarterback in his senior year.
 He enrolled at Ohio State University in 1941.
 He enlisted in the United States Marine Corps in 1943, served 53 months in the military and earned a Bronze Star for his service in the Pacific Theater before returning to Ohio State.
 He played college football as quarterback for the Ohio State Buckeyes football team in 1946 and 1947.
The 2002 Ohio State Buckeyes football team was the national champion of the 2002 NCAA Division I-A football season.
 The team was the first in Division I-A (now Division I FBS) history to finish its season at 14–0, and the second to win 14 games, following BYU's 14–1 season in 1996.
 The Buckeyes' record-tying 14 wins has since been matched by multiple teams.
 Led by co-MVPs junior quarterback Craig Krenzel and sophomore wide receiver/cornerback Chris Gamble, freshman standout tailback Maurice Clarett, and senior safety Mike Doss, the Buckeyes won the 2003 Fiesta Bowl, which was also the 2003 BCS National Championship Game.
The Ohio State Buckeyes football statistical leaders are individual statistical leaders of the Ohio State Buckeyes football program in various categories, including passing, rushing, receiving, total offense, defensive stats, and kicking.
 Within those areas, the lists identify single-game, single-season, and career leaders.
 The Buckeyes represent the Ohio State University in the NCAA's Big Ten Conference.
The 2012 Ohio State Buckeyes football team represented The Ohio State University in the 2012 NCAA Division I FBS football season.
 It was the Buckeye's 123rd season overall, the 100th as a member of the Big Ten Conference and the second as a members of the Big Ten Leaders Division.
 The team was led by head coach Urban Meyer in his return to coaching after retiring from Florida in 2010 due to health concerns.
 The Buckeyes played their home games at Ohio Stadium in Columbus, Ohio.
 The Buckeyes finished the season undefeated with 12 wins (12–0 overall, 8–0 in the Big Ten), Big Ten Leaders Division champions and ranked third in the AP Poll.
 Due to findings of an investigation conducted by the NCAA during the previous season, Ohio State was ineligible for both the Big Ten Championship Game and an appearance in a bowl game for the 2012 season.
Aurealius Thomas (born April 6, 1934), sometimes spelled Aurelius Thomas, is a former American football player.
 A native of Columbus, Ohio, Thomas was six feet, one inch tall and weighed 204 pounds.
 He attended the Ohio State University where he played college football at the guard position for the Ohio State Buckeyes football team from 1956 to 1957.
 He was selected by the All-America Board, the American Football Coaches Association, the Associated Press, and the Football Writers Association of America as a first-team guard on their respective 1957 College Football All-America Team.
 He averaged 57 minute a game during the 1957 season, and Ohio State coach Woody Hayes said, "For consistent play on both offense and defense, there is no better guard in college football today."
 Thomas was drafted in 1958 by the Pittsburgh Steelers, but he was released by the Steelers in late August 1958 before the start of the regular season.
 After graduating from Ohio State, Thomas worked as a teacher for several years, worked for New York Life Insurance Company and later started his own insurance brokerage business in Columbus, Ohio.
 He was elected to the College Football Hall of Fame in 1989.
The 2003 Ohio State Buckeyes football team represented Ohio State University in the 2003 NCAA Division I-A football season.
 The team's head coach was Jim Tressel.
 The Buckeyes played their home games in Ohio Stadium.
 Ohio State finished the season with an overall record of 11–2 and placed second in the Big Ten Conference with mark of 6–2.
 The Buckeyes concluded their season with a victory over Kansas State in the Fiesta Bowl.
John Bernard Christian Eckstorm (October 22, 1874 – October 28, 1964) was an American football player and coach.
 He served as the head coach at Ohio State University from 1899 to 1901, compiling a record of 22–4–3.
 Eckstorm was the first Ohio State Buckeyes football coach to have a winning record at the school.
 In his first season in 1899, the Buckeyes went 9–0–1 giving OSU their first undefeated season in school history.
 The next season, he led Ohio State to a tie against Michigan in the second meeting of the two schools.
Boyd Vincent Cherry (March 6, 1893 – November 14, 1970) was an American football and basketball player.
 He played college football and basketball at Ohio State University.
 In 1914 he became the first Ohio State Buckeyes football player to receive All-American honors and the first to receive first-team all-conference honors.
 After graduating from Ohio State in 1915, he was employed for more than 25 years by the Kinnear Manufacturing Company in Columbus, Ohio.
 He was born in Newark, Ohio, in 1893, and he died in 1970 at age 77 in Fort Myers, Florida.
Craig Krenzel (born July 1, 1981) is a former American football quarterback.
 He played college football at The Ohio State University.
 As the starting quarterback, he led the 2002 Ohio State Buckeyes football team to a national championship.
 He played professionally in the National Football League (NFL) for one season, in 2004, with the Chicago Bears.
 Krenzel is currently a radio commentator for WBNS 97.1 The FAN in Columbus, which broadcasts the Ohio State Buckeyes football games.
Maurice Edward Clarett (born October 29, 1983) is a former American football running back who played for the Ohio State Buckeyes football team.
 He also played professionally for the Omaha Nighthawks of the United Football League.
 During his freshman year at Ohio State University in 2002, he helped lead the Buckeyes to a national championship.
 In a widely unexpected move, Clarett was drafted on the first day of the 2005 NFL Draft with the final pick of the 3rd round (#101 overall) by the Denver Broncos.
 He is well known for unsuccessfully challenging the NFL's draft eligibility rules requiring a player to be three years removed from high school and for his tumultuous life outside of football, including his dismissal from Ohio State, several arrests, and imprisonment.
 Since his release, he has begun work on an entrepreneurial career, along with being a public speaker.