Johnny Manziel has been officially ruled out of the team's season finale with a concussion. Coach Mike Pettine announced the move, saying that the quarterback will miss the Week 17 match against the Pittsburgh Steelers because of the head injury he sustained during the team's loss to the Kansas City Chiefs last weekend.

After the game, the Browns said that the 23-year-old quarterback reported to the facility and complained about concussion-like symptoms. In Manziel's stead, Austin Davis will make his second start of the season. He will possibly be backed up by wide receiver Terrelle Pryor, who worked as a quarterback during the club's practice on Wednesday.

However, a number of NFL fans have aired their opinions over the Internet and expressed doubts about Manziel's concussion, especially after he appeared to come out of last Sunday's game unscathed.

A report by the New York Post listed some the fans' tweets claiming that the reason for the quarterback being out is because of a hangover and not a concussion. Earlier this year, he spent 10 weeks in a treatment facility for several months, and he stayed away from social media until about midway through the season.

In October, Manziel was questioned by police after responding to 911 calls reporting that the player had been driving a high rate of speed on a highway. There are also claims that he had allegedly been hitting his girlfriend, ESPN reported.

It is a rather disappointing way to end the Heisman Trophy recipient's season, who finishes the last one with 129-of-223 for 1,500 yards, seven touchdowns, and five interceptions through the air and 37 rushes for 230 yards on the ground. Pettine said that as Manziel's second season ends, he will not be complete as a player until he is complete as a person off the field.

"I want to make sure all our players are in good shape as people first, players second. Because I don't think you can be as effective as you can be as a player if things are not right off the field. And he's a good example of that," the coach said Thursday.

Meanwhile, Pettine himself could be down to his final days as the Cleveland Browns' head coach. Rand Getlin of the NFL.com reports that there is a "sense" around the Browns now that Pettine is set to be fired by owner Jimmy Haslam after this week's matchup against the Steelers.

A season finale match versus the Pittsburgh Steelers is a bad sign for a struggling Browns coach, Cleveland.com observes.  The last four were terminated after season-ending losses to Pittsburgh, and if the trend continues, Pettine will likely become the fifth.

Aside from the head coach, Browns owner Jimmy Haslam is also rumored to fire general manager Ray Farmer as early as Sunday night. League sources claim that Haslam has already been preparing the groundwork for their replacements.

Coming into the Week 17 finale with the Steelers, the Browns are 3-12 and have lost nine out of their last 10 games. The club also ranks second to the last in both points for and points against in the NFL this season.