In 1993–94, as a rookie, Arnott played 78 games as a left winger, scoring 68 points and finishing as the runner-up to future teammate Martin Brodeur for the Calder Memorial Trophy for rookie of the year. On January 4, 1998, Arnott was traded to the New Jersey Devils along with Bryan Muir in exchange for Valeri Zelepukin and Bill Guerin. As a member of the "A Line" on the Devils with Patrik Eliáš and Petr Sýkora, he led the team to the 2000 Stanley Cup championship, scoring the Cup-winning goal at 8:20 of double overtime in Game 6 against the Dallas Stars.
On March 19, 2002, Arnott was traded to the Dallas Stars with Randy McKay in exchange for Joe Nieuwendyk and Jamie Langenbrunner. In 2005–06, Arnott had a career high 76 points for Dallas and scoring 32 goals, the most since his rookie season, in which he had 33. He also set a career high of 44 assists. In the off-season, he signed a five-year, $22.5 million contract as an unrestricted free agent with the Nashville Predators. He was named the Predators' fourth captain in the franchise's history on September 12, 2007.
On June 19, 2010, Arnott was traded back to his Stanley Cup-winning team, the New Jersey Devils, in exchange for forward Matt Halischuk and a second-round pick in 2011. This was the first-ever trade between the Devils and the Predators. With the Devils, Arnott played alongside captain Jamie Langenbrunner, his original counterpart in his trade to the Stars in 2002.
On February 28, 2011, Arnott was again traded away from the New Jersey Devils, this time to the Washington Capitals, in exchange for Dave Steckel and a second-round pick in 2012.
On March 9, 2011, Arnott recorded his 900th career point against the team that drafted him, the Edmonton Oilers, in a 5–0 shutout victory. On April 2, 2011, he scored his 400th career goal in a 5–4 overtime victory against the Buffalo Sabres. On July 6, 2011, Arnott signed a free agent contract with the St. Louis Blues.
After scoring 17 goals with 17 assists in 72 games during the 2011–12 season, the Blues opted not to re-sign Arnott. On January 26, 2013, he then signed a one-year deal with the New York Rangers worth approximately $1.6–$1.7 million. The deal, however, was not finalized when Arnott failed his physical and was not cleared to play by Rangers' doctors.
On November 5, 2013, Arnott announced his retirement from the NHL after 18 seasons in the NHL. In October 2014, it was announced that Arnott was hired as a part-time scout for the St. Louis Blues.
| Played for | Edmonton Oilers New Jersey Devils Dallas Stars Nashville Predators Washington Capitals St. Louis Blues | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| National team |  Canada | |||||||||||||||
| NHL draft | 7th overall, 1993 Edmonton Oilers | |||||||||||||||
| Playing career | 1993–2013 | |||||||||||||||
Medal record
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Awards
- Named to the NHL All-Rookie Team in 1994
- Played in the NHL All-Star Game in 1997 and 2008
- Won a Stanley Cup with the New Jersey Devils in 2000
- Set the Nashville Predators record for most goals in one season, 33 in 2008–09. The record has since been surpassed by Viktor Arvidsson when he scored his 34th goal of the 2018–19 season on 4/7/2019.
- Scored the overtime Stanley Cup-winning goal with the New Jersey Devils in 2000