After a successful college football career with the TCU Horned Frogs, the San Diego Chargers selected him as the fifth overall pick in the 2001 NFL draft.

He spent nine years with the Chargers, earning five Pro Bowl appearances, three Associated Press first-team All-Pro nominations, and two NFL rushing titles.

These feats won him the NFL MVP award, but San Diego suffered an upset defeat in their playoff opener, and Schottenheimer was fired shortly afterwards.

[5][6] He was named to the state all-star football team in 1997, which included future San Diego teammates Drew Brees (Austin Westlake) and Quentin Jammer (Angleton).

[98][99] In week 7, he tied Marion Butts's record with 39 carries in a game, rushing for 153 yards and scoring the winning touchdown as San Diego beat the eventual AFC champion Oakland Raiders 27–21 in overtime.

[108] Tomlinson nonetheless passed Means' franchise record for rushing yardage in a season with three games still to play,[109] and finished with 1,683 yards,[110] second-most in the league.

[110] Tomlinson was rewarded for his performances with his first Pro Bowl nomination (together with Junior Seau, he was one of only two Chargers so honored),[117] as well as being named an Associated Press (AP) 2nd-team All-Pro.

[118] During the 2003 offseason, San Diego signed Lorenzo Neal, a fullback who had blocked for 1,000-yard rushers in each of his previous six seasons, and was coming off his first Pro Bowl nomination.

"[140] However, he was named a Second-team Associated Press All-Pro for the second season in a row,[141] and was runner-up to Jamal Lewis for the AP Offensive Player of the Year Award with eight votes.

[146] San Diego clinched the AFC West division in week 15, with a 21–0 win in the snow over the Cleveland Browns; it was their first playoff berth since 1995, ending an eight-year drought.

"[186] However, Tomlinson would suggest in a 2016 interview with ESPN that the switch cost San Diego a Super Bowl win, stating that Rivers was too inexperienced at the time.

[194][195][196] In the following game, he caught one touchdown and threw for another as San Diego erased a 14-point, 4th-quarter deficit against the Kansas City Chiefs, though they went on to lose 30–27 to a late field goal.

[231] Tomlinson was also named co-winner of the Walter Payton Man of the Year Award alongside Brees, now quarterback of the New Orleans Saints,[232] and was voted to his fourth Pro Bowl.

[236] After the game, the usually mild-mannered Tomlinson shouted at New England players celebrating on the Chargers midfield logo at Qualcomm Stadium by mocking Merriman's sack dance, and suggested Patriots head coach Bill Belichick might be to blame in a post-match interview.

[240] Norv Turner, who was the San Diego Chargers offensive coordinator in Tomlinson's rookie season, replaced Schottenheimer as head coach a week later.

[249] In a week 12 win against the Kansas City Chiefs, Tomlinson gained 177 yards on 23 carries and scored twice, passing Walter Payton on the all-time career rushing touchdown list with his 111th.

"[266] The following week, Tomlinson carried seven times for 28 rushing yards and caught a 20-yard pass, before injuring his knee and leaving the game in the second quarter of the Chargers 28–24 Divisional Round win against the Indianapolis Colts.

[269][270] Tomlinson attempted to play through his injury in the following week's AFC Championship, and had two carries for five rushing yards and a one-yard catch but re-injured the knee and sat out the rest of the game.

"[276] Neal, who had missed time in 2007 with a broken fibula, was released by the Chargers during the offseason, leaving rookies Mike Tolbert and Jacob Hester to serve as Tomlinson's lead blockers.

[301] When Tomlinson release a statement expressing his desire to remain in San Diego, Smith appeared to mock him when he responded to an interview question using very similar wording.

[340] Tomlinson chose to sign with New York because of his familiarity with the system of offensive coordinator Brian Schottenheimer, his enthusiasm for the defense- and run-focussed philosophy of head coach Rex Ryan, and because he felt that the team offered him the best chance to win a championship.

[349][350][351][352] He continued to move up the NFL's career rushing yardage leaderboard during the season, passing Tony Dorsett and Eric Dickerson to reach sixth place.

They were heavy underdogs, having lost 45–3 to the Patriots in week 13;[356][357][353] Tomlinson spoke of the matchup as an opportunity to redeem himself after having to leave the AFC Championship Game against the same team three seasons earlier.

[358] In the AFC Championship Game against the Pittsburgh Steelers, the Jets were down 24–10 in the fourth quarter when Tomlinson was unable to score a touchdown on a fourth-and-goal from the one-yard line.

Missing part of the game due to illness, he gained 51 yards from scrimmage; of beating the Chargers after they'd released him, he commented, "I'd be lying if I said this didn't add some extra satisfaction.

[216] In week 14, the Jets defeated the Kansas City Chiefs 37–10 to improve their record to 8–5,[371] but lost their following two games to the Philadelphia Eagles and the New York Giants, and needed to win their regular season finale at Miami to have any chance of making the playoffs.

[381] Former teammates including Rivers, Gates and three offensive linemen from his 2006 season were present at Tomlinson's farewell press conference, as were his wife, mother and children.

[397] In 2005, Schottenheimer described Tomlinson as the finest running back he'd seen, arguing that past greats such as Jim Brown and Gale Sayers hadn't had to contend with defenders of the same size and speed.

[442] In April 2007, CNBC reported that Tomlinson turned down a request to become the cover athlete for EA Sports' Madden NFL 08 video game, as the money offered was not enough to justify the promotional work involved.

The foundation helps high school and college students, provides meals for people who are homeless or poor, and raises money for after-school programs and other causes.