NFL notes: Cam Newton playing at his best in four quarter for Panthers

One day after doctors checked Panthers quarterback Cam Newton for a possible concussion, Carolina coach Ron Rivera defended the process in a heated exchange with reporters.

Rivera said angrily not to "question my integrity" in the team's handling of Newton after a big helmet-to-helmet hit he took in the third quarter of Sunday's 41-38 victory over New Orleans.

Saints linebacker Michael Mauti hit Newton near the goal line, and Newton was slow to get up. The Panthers ran three more plays before Newton went to the locker room to be tested for a concussion.

Newton later took another big hit to the head from Hau'oli Kikaha. He complained of neck pain after the game.

The St. Louis Rams fired offensive coordinator Frank Cignetti.

Rob Boras, assistant head coach/offense and tight ends coach, will take over his duties.

St. Louis (4-8) has lost five in a row and had a season low for points in a 27-3 loss to the Arizona Cardinals on Sunday.

"[Cignetti]'s a good man," Fisher said. "But we scored 13 points or less in seven of our eight losses. … We're all at fault."

Lawyers for the NFL Players Association told a federal appeals court that NFL Commissioner Roger Goodell was making a "sweeping grab for power" in the "Deflategate" controversy.

The lawyers made the claim in papers filed Monday with the 2nd U.S. Circuit Court of Appeals in Manhattan.

The appeals court is hearing the NFL's appeal of a judge's ruling that nullified the league's four-game suspension of Patriots quarterback Tom Brady.

• Broncos quarterback Peyton Manning will throw outdoors this week as he begins his comeback from a torn plantar fascia in his left foot.

• Quarterback Johnny Manziel will start Sunday when the Browns host the 49ers, ESPN reported.