After 15 seasons in Cincinnati that have made him the longest-tenured head coach in franchise history, Marvin Lewis is planning to leave the Bengals after this season to pursue opportunities elsewhere, league sources told ESPN.

As he has done in the past, Lewis willingly opted to enter 2017 on the final year of his contract, but unlike in other years, this time he is planning to leave Cincinnati, sources said.

Finally Changing His Stripes? Hired in 2003, Marvin Lewis is the second-longest-tenured coach in the NFL, trailing only the Patriots' Bill Belichick. Longest tenures by current head coaches Coach Team Season Hired Bill Belichick Patriots 2000 Marvin Lewis Bengals 2003 Mike McCarthy Packers 2006 Sean Payton* Saints 2006 Mike Tomlin Steelers 2007 * Suspended for 2012 season

With a flurry of head-coaching openings expected in the coming weeks and a shortage of obvious head-coaching candidates with experience, Lewis is likely to be on teams' short lists of candidates, league sources said.

If a head-coaching job does not materialize, sources said Lewis would be interested in working in another team's front office or as a coaching adviser for a former Bengals assistant coach who has gone on to become a head coach, such as Mike Zimmer, whose Minnesota Vikings host the Bengals on Sunday.

Lewis dismissed the report before Sunday's game, telling Bengals.com there was "nothing to it."

After the Bengals' 34-7 loss to the Vikings, Lewis was asked if the report was accurate.

"No. It's the same report that you guys have been reporting on all season," Lewis said. "Nothing's changed since August. It's just the speculation that people keep throwing out there. We're all wasting time talking about that."

"I have not made any decisions," he added.

Not only is Lewis' contract up, but so are those of most, if not all, of the Bengals' assistant coaches. The Bengals have declined to give contract extensions to their assistant coaches, and some are unhappy with the way they have been treated financially, sources said.

Amid the uncertainty and potential change, the Bengals are likely to undergo a major overhaul to their coaching staff. Some assistants could wind up staying, but many are expected to leave along with Lewis.

"We are wasting time, that's all," Lewis said during his postgame comments. "It affects people around you, which is unfortunate. And I understand that's what drives media. But people just throw things out. Supposedly they throw things out Monday night, and everybody has to respond. And who everybody wants to be first, they don't necessarily have to be accurate, but they want to be first."

Despite regular-season success, Bengals coach Marvin Lewis has yet to win a postseason game. Joe Robbins/Getty Images

Browns coach Hue Jackson said after his game that he "would take Marvin in any way I can take him," when asked if he'd consider hiring Lewis as an adviser.

"I know what Marvin is, but again, I don't want to get into all of those things," Jackson said. "I think he deserves the right to go out his way. Talking about what he may do and where he would go, I don't think that is the time to do that right now."

When Lewis leaves the Bengals, it will mark the end of a chapter in which Cincinnati returned to prominence but failed to advance in the postseason.

When he accepted the job on Jan. 14, 2003, the Bengals were one of the NFL's laughingstock franchises, coming off the worst season in franchise history. Lewis beat out Tom Coughlin and Mike Mularkey for the job and almost immediately remade and elevated the roster.

Marvin Lewis' Playoff Pain Marvin Lewis hasn't been able to help the Bengals advance in the postseason. Cincinnati hasn't won a playoff game since the 1990 season, the longest active drought in the NFL. Worst postseason coaching records (min. 5 games) Coach Record Marvin Lewis 0-7 Jim Mora 0-6 Sid Gillman 1-5 Jack Pardee 1-5 Wade Phillips 1-5 -- Elias Sports Bureau

Lewis helped make the Bengals relevant again, but he never led the team to a postseason win. His seven playoff losses, each as disappointing as the next, made Lewis the only head coach in history to lose his first seven postseason games, according to the Elias Sports Bureau.

But Lewis has compiled a 123-111-3 record that, at a time in which the Pittsburgh Steelers and Baltimore Ravens have been among the NFL's elite franchises, was good enough to win the AFC North four times.

The Bengals' 2017 season has been defined by disappointment and injuries. When the 5-8 Bengals face the Vikings, they will be without starting cornerbacks Adam Jones, who is on injured reserve, and Dre Kirkpatrick, who has a concussion. Bengals linebackers Vontaze Burfict (concussion), Kevin Minter (hamstring) and Nick Vigil (ankle) also are out. They are expected to get safety Shawn Williams back from a hamstring injury.