Patrick Mahomes gets in Rashee Rice's face after missing potential game-winning throw

Tempers flared on the Kansas City Chiefs sideline as regulation ended in Super Bowl 58.

Patrick Mahomes and his lead receiver Rashee Rice exchanged words after the quarterback targeted Travis Kelce on the final attempt of regulation.

The rookie wanted the ball and it's easy to see why. He could have won the game with a touchdown on that play if Mahomes had looked his way. Instead, the Chiefs had to settle for a game-tying field goal to force overtime.

Patrick Mahomes and Rashee Rice weren't only Chiefs sideline conflict

That wasn't the only explosive moment on the Kansas City sideline during the Super Bowl. In the first quarter, Kelce bumped head coach Andy Reid while apparently fuming over a playcall.

In the biggest game of the season, with legacies on the line, you can understand some emotionality on the sideline. Rice is a rookie. He's never had the chance to catch a Super Bowl-winning touchdown. And he never may again.

Still, these are the moments that can make or break a relationship and a team. Too many of those sideline blowups can lean towards toxicity in the locker room if they're not kept under control.

The 49ers frustrated the Kansas City offense for much of the first half. After San Francisco took a 10-0 lead on a Jake Moody field goal and a Christian McCaffrey trick-play touchdown, Harrison Butker hit a field goal just before halftime to make it 10-3.

The Chiefs owned the third quarter with a Super Bowl-record 57-yard field goal and a Marquez Valdes-Scantling touchdown catch to take a 13-10 lead. The 49ers responded with a Jauan Jenning touchdown but a blocked extra point gave KC the opportunity to trade field goals and then boot through the game-tying kick with three seconds left.

Both Mahomes and Rice wanted more. They just didn't connect.