The Raiders told Sebastian Janikowski they do not intend to bring him back next season, ESPN reported Wednesday, parting ways with their longest-tenured player after 18 years.

The left-footed kicker known as “Seabass” is the franchise’s career leader in points (1,799) and games played (268). He will become a free agent in March, shortly after his 40th birthday.

The move rules out a possible reunion between Janikowski, who missed all of last season with an injured back, and head coach Jon Gruden. Janikowski was drafted by the Raiders from Florida State in the first round in 2000, during Gruden’s first stint as head coach.

Only two other members of that 2000 draft class are active in the NFL. One is punter Shane Lechler, who also was drafted by Oakland and played the past five seasons with the Texans. The other is New England quarterback Tom Brady, who just played in his eighth Super Bowl.

Over 17 seasons, Janikowski became a fixture on special teams, converting 80.4 percent of his field-goal attempts (414 of 515) and 98.9 percent of extra-point tries.

In the Raiders’ 2011 season opener at Denver, Janikowski tied what was then the record for the longest field goal in NFL history: 63 yards, equaling a mark shared by Tom Dempsey and Jason Elam. Denver’s Matt Prater broke that record with a 64-yarder in 2013.

Janikowski’s 55 field goals of 50-plus yards are the most in NFL history, according to Pro Football Reference. He ranks 10th overall in field goals made and 12th in attempts.

His last appearance came in the team’s second preseason game in August. Shortly before the season started, Janikowski and the Raiders agreed to rework his contract, reportedly settling on a figure of $3 million guaranteed. Janikowski spent the season on injured reserve.

Giorgio Tavecchio, who took over kicking duties, converted 16 of 21 field-goal attempts and 33 of 34 extra-point tries. The Raiders can tender Tavecchio, who is an exclusive-rights free agent, a contract offer when free agency begins March 14.

Matt Kawahara is a San Francisco Chronicle staff writer. Email: mkawahara@sfchronicle.com Twitter: @matthewkawahara