A rough day for corporate accountability in the NFL

THE NFL CONTROLS THE CONCUSSION BUSINESS: NFL donations to brain research benefit league-linked doctors, raise worries about influence on science. Outside the Lines released a major report Thursday that reveals serious reservations among the scientific community about the role being played by the NFL, the biggest funder of brain research. "This is a recipe for disaster," said one scientist. Another compared it to the tobacco industry.

STATE OF DENIAL: Another NFL doctor refuses to acknowledge concussion reality. At the NFL's annual press conference on health and safety, one member of the NFL’s Head, Neck & Spine Committee told reporters that there was no link between playing football and degenerative brain disease.

PEYTON'S PRIVATE EYES: Days before the AL Jazeera report accusing Peyton Manning of using HGH that was shipped to his house in his wife's name, he dispatched two private investigators to his accuser's parents' house to dig further into the allegations. A day later Charlie Sly recorded a video recanting the allegations.

NFL INVESTIGATING MANZIEL: Police report alleges Johnny Manziel told girlfriend "shut up or I'll kill us both." New details about the Jan. 30 incident have come to light just as Dallas and Fort Worth police announced that they had no plan to charge Manziel and closed the investigation. The NFL is still conducting its own investigation into the incident.

TEBOW UPDATE: Tim Tebow says he is rooting for the Denver Broncos to win Super Bowl 50.

SNOOP MEETS CAM: Snoop Dogg had the best question for Cam Newton at media day. This video is great.

SUPER SUPER BOWL PREVIEW: This Super Bowl 50 preview is so amazing it needs its own preview. This week on the podcast: Narratives! Playbooks! Xs and Os! Prop bets! We've got it ALL!

HOW TO BEAT THE PANTHERS: We asked Matt Ryan how to beat the Panthers. Matt Ryan and the Falcons were the only team to beat the Panthers in the regular season. Now visiting the Super Bowl, Ryan talks with SB Nation about what it takes to beat Carolina, his favorite rapper and more.

MIKE CAREY DOESN'T CARE: Mike Carey knows you think he sucks, but he has a process that ensures he doesn't. Mike Carey, CBS' NFL officiating expert, is in sync with replay decisions 90 percent of the time. He uses a hotline between himself, the NFL and Mike Perreira, plus a keen knowledge of the rules, to get there.

EYEING GREATNESS: Von Miller and the Broncos defensive line eyeing "another chance at greatness." The Broncos defensive line just keeps doing the same thing it's been doing every week all season long. They're counting on that basic approach to bring home a Lombardi Trophy.

SCORE: What it's like to score a Super Bowl touchdown. Six pros remember their big moment.

PEYTON IS FINE: Peyton Manning hasn’t been as bad as you think. Sure, the Broncos quarterback isn't playing as well as he did in 2013, but he's not getting enough credit for making some smart throws during Denver's playoff run. That could be the difference against the Panthers. He was certainly dealing it at practice on Thursday.

DIVERSITY IN THE NFL: The NFL will institute a Rooney Rule for women in executive positions. NFL commissioner Roger Goodell announced the news at the NFL Women's Summit.

SUPER BOWL LOSERS: No team is better at losing Super Bowls than the Broncos.

DEMARCO TO DALLAS? Could DeMarco Murray go back to Dallas? A new report seems to make that a real possibility.

HANGIN' WITH BEAST MODE: Marshawn Lynch plays Doom with Conan O'Brien, Von Miller, and Josh Norman. It's baaaaaaaaaackkkkkkkk.

DRAFT RUMOR: Jared Goff was reportedly asking Browns players what Cleveland is like. Welp.