Cameras had captured Eli looking glum while the rest of his family celebrated after the Broncos' win.
But Peyton insisted his brother was nothing but supportive.
“Eli’s just like me," the quarterback told CBS Sports. "Eli is analyzing the game. He's thinking about whether we were going to go for two. Whether it was going to be reviewed. He wasn't gonna to relax until that final second ticked off. I've had a great chance to celebrate with Eli. He's very happy and proud of me just like I’ve always been of him.”
He also denied any sibling rivalry, saying: “We don't do that, that's not what we do. Maybe you guys, your brothers do that, that's not what we do."
Meanwhile, Carolina Panthers quarterback Cam Newton is getting heat for walking out of his post-game press conference after just three minutes.
There's now speculation it was because he overheard a Broncos cornerback bragging about the team's winning strategy: “Load the box, force y'all to throw the ball. Can you throw the football? That was the gameplan.”
Those comments may have pushed the Panthers star over the edge when he met with reporters.
But is Newton the only sore loser?
After Super Bowl 44 in 2010 when Peyton Manning was with the Indianapolis Colts, he faced a crushing defeat by the New Orleans Saints. He rushed off the field without shaking hands with the opposing quarterback Drew Brees.