Cadillac Williams

Williams entered the 2005 NFL Draft and was selected with the fifth pick of the first round by the Tampa Bay Buccaneers.[15] He signed a five-year contract worth $31 million.

Jeff Reynolds of Pro Football Weekly predicted Williams was the rookie most likely to have the greatest impact in the 2005 NFL season, writing that "at the Senior Bowl, Jon Gruden was salivating over this kid. He pulled him out real early. Don't think that was a coincidence. He's the offense. Gruden has set it up, Cadillac or bust".

The first half of the season for Williams was an up and down affair. Williams rushed for 434 yards in his first three weeks, setting records as the first rookie running back to ever have three consecutive 100 yard games, and rushing for the most yards in the first three weeks of a career, a record previously held by Alan Ameche of the 1955 Baltimore Colts. Williams was also named rookie of the week for the first three weeks of the season and rookie of the month for September. His shoes and gloves from week three were subsequently retired to the Football Hall of Fame in Canton, Ohio.[16] In week four however, Williams dealt with injuries to his ankle and arch in his right foot, causing him to miss two weeks. In the next four games he played, including the game in which he was injured, Williams only rushed for a combined 82 yards on limited carries. However, in his next four games, he averaged over 100 yards per game (408). In his rookie season, Williams tallied six 100-yard games in 14 starts, and led all rookies in total rushing yards (1,178), rookie of the week honors (3), and finished second, behind Brandon Jacobs for rushing touchdowns (6).

On January 4, 2006, Williams was awarded the Associated Press NFL Offensive Rookie of the Year award. He drew 47 votes of a nationwide panel of 50 sports writers and broadcasters who cover the NFL. He beat former running mate Ronnie Brown of Miami, who received one vote. Tight end Heath Miller of Pittsburgh and offensive lineman Logan Mankins of New England also received one vote. On February 2, 2006, Williams was announced as the NFL Rookie of the Year Award winner based on the votes of over 1,000,000 visitors to NFL.com.

Williams was unable to match the success of his rookie campaign in the 2006 NFL season, as he failed to reach the 1,000 yard mark. His reduced production was attributed to poor offensive line play and an injury that nagged him all year.

In October 2007, Williams suffered a torn patellar tendon to his right knee against Carolina, which required surgery and ended his season. Doctors were doubtful he would come back to full strength after this devastating injury. Williams, however, said that he had "no doubt" that he would play in 2008.

In mid-season of 2008, Williams began practicing with the team and was listed as questionable on the official injury report. In November, he was taken off the Physically Unable to Perform list and added to the active roster. He played in his first game in 14 months against Detroit. On November 30 against the Saints, he scored his first touchdown since his return. One month later, however, during the final game of the season on December 28, Williams suffered another torn patellar tendon, this time in his left knee.

The second tear was not as severe as the first, but Williams again endured surgery and an intense period of rehab to get back on the field. He returned to game action during the 2009 preseason and was the Bucs' starting running back to open the regular season, becoming the first NFL player to return from patellar tendon tears in both knees.[17] On December 27, Williams had his first 100-yard rushing game in two seasons for the Tampa Bay Buccaneers and finished with 823 yards, the second highest total of his NFL career.. Williams was narrowly edged for the AP 2009 Comeback Player of the Year Award by Tom Brady, finishing second with 15 votes. He rushed for 821 yards on 210 carries with a 3.9 average and four touchdowns. He also caught 29 passes for 219 yards and 3 touchdowns.

After Williams' turnaround 2009 Tampa Bay Buccaneers season, in which he played in all 16 games for the first time in his career, the Tampa Bay Buccaneers had high hopes for their former National Football League Rookie of the Year Award winner. However, due to the emergence of undrafted rookie sensation LeGarrette Blount, Williams found himself cemented as primarily the third down running back for the latter half of the 2010 Tampa Bay Buccaneers season. Williams was used as a passing threat on third down and finished the season with 46 receptions for 355 yards and one touchdown (a come-from-behind, game-winning catch from Josh Freeman with ten seconds left in the fourth quarter on October 24, 2010, against the St. Louis Rams). He finished the 2010 NFL season with 125 rushing attempts for 437 yards and two touchdowns (one against the San Francisco 49ers and one against the Carolina Panthers), helping his team to a 10–6 record. The Buccaneers missed the 2010-11 NFL playoffs and Williams became an unrestricted free agent in 2011.

On August 3, 2011, Williams signed with the St. Louis Rams to be the backup for Steven Jackson. In the 2011 regular season opener, Williams had 91 yards on 19 carries against the Philadelphia Eagles. Williams rushed effectively throughout the season for St. Louis, mainly in a backup capacity. He finished the year with 361 rushing yards and 4.1 yards per carry. He also scored one rushing touchdown, in the final game of the season against the San Francisco 49ers.[18]