Kyle Shanahan soured over Browns

Friction among the coaching staff and front office of the Cleveland Browns has left offensive coordinator Kyle Shanahan considering his options elsewhere, Cleveland.com has reported, citing multiple league sources.

Shanahan is among several candidates to fill the head-coaching vacancy with the Buffalo Bills and reportedly will interview for the job Thursday morning.

Shanahan hadn't notified his immediate camp about desperation to leave the Browns as he prepared for the Bills interview, which was to take place in South Florida, a source told ESPN.com's Jeremy Fowler on Tuesday night. The Bills are the only team known to be considering Shanahan for a head-coaching job.

A Browns front-office source, speaking to ESPN.com's Pat McManamon, questioned the report, calling it "sour grapes" from a disillusioned staff member.

According to the Cleveland.com report, Shanahan also is enticed by the idea of coaching again under his father, Mike Shanahan, with whom he worked for four years on the Washington Redskins before both were fired after last season.

The Bills, San Francisco 49ers and Oakland Raiders already have interviewed Mike Shanahan and would consider hiring the father-son duo with Mike as head coach and Kyle as offensive coordinator, Cleveland.com's report said.

Mike Shanahan has another interview slated with the Chicago Bears, according to the report.

The specifics of the dysfunction that soured Kyle Shanahan on the Browns were said to be varied and include the personnel side of the team and the coaches perceiving several key issues in different lights.

Cleveland.com reported one source as saying some coaches became angered when play calls were recently requested or suggested via text from the press box by a high-ranking non-coaching staff member.

The Browns' situation at quarterback also has provided significant friction, Cleveland.com reported, especially in the wake of Johnny Manziel's lagging performance against the Cincinnati Bengals after Shanahan took Manziel under his wing in the leadup to a 30-0 loss.

The disconnect also stems from a belief that the front office placed clear, although indirect, pressure to have Manziel play, a source close to the situation has told ESPN.com. That pressure never came in the form of an order but was tangible and increased as the season went on.

Although not every offensive coach was solidly in Brian Hoyer's corner, the offensive staff is unhappy and disillusioned over the pressure about Manziel from non-football people and the way the season ended, the source told ESPN.com.

Offensive coaches know they are looking at a 2015 season against AFC West and NFC West teams with no defined quarterback and with in-the-building dysfunction, and they realize they're staring at a tough season that could end with them being fired, according to the source. There might be some desire on their part to get out now, ahead of the curve.

"Every offensive coach knows what they are looking at next season," the source said.

Information from ESPN.com's Jeremy Fowler and Pat McManamon was used in this report.