Mary Kouw/CBS

Super Bowl LV is arguably the most anticipated Super Bowl in history as Tom Brady and Patrick Mahomes square off in a battle of the NFL's hierarchy. Brady is going for that unprecedented seventh Super Bowl title while Mahomes is seeking to become the youngest player to win two Super Bowls -- besting the record Brady set 18 years ago. 

In addition to all the hype surrounding Super Sunday, this will be the 21st Super Bowl broadcast on CBS -- the most of any network. Jim Nantz and Tony Romo will be calling the game, the second Super Bowl for the pair -- a perfect fit for a matchup that is expected to live up to the hype. Fun fact about this year's Super Bowl: Pat Summerall and John Madden called their second Super Bowl for CBS in Tampa and Nantz and Romo are calling their second Super Bowl in Tampa. 

The GOAT conversation will continue if Mahomes beats Brady. If Brady wins, Romo knows the game will be over. 

"I really think this game is a legacy game," Romo said on a Super Bowl conference call with CBS Sports. "This is going to be one of the great matchups in sports history. This is what you talk about with your friends. Could you imagine if Michael Jordan got his team to the Finals against LeBron -- who is becoming the face of the league? We're getting that in this Super Bowl. It's like Jack Nicklaus against Tiger Woods. There's nothing else I could find. 

"The fact that Patrick Mahomes is somehow in this discussion shows you how amazing this guy is. There's a chance for Patrick Mahomes playing this game, to climb the ladder. If Mahomes wins, he keeps that door open. 

"If Brady wins, I don't know how anyone can top him." 

Nantz has called plenty of Super Bowls with Brady over the years. He was the host of "The NFL Today" when Brady led the New England Patriots to a win in Super Bowl XXXVIII and called Brady and New England's Super Bowl LIII victory over the Los Angeles Rams. Brady's longevity has made Nantz run out of his trademark superlatives to describe his dominance. 

"Two years ago when we did that game -- if Brady wins -- is this going to be his last game," Nantz said when he and Romo called Super Bowl LIII. "We felt pretty good we did Tom Brady's last Super Bowl. Tony and I did our goodbyes on the air after the wild-card loss last year. Now we're going back to the Super Bowl and here he is again! If anyone out there has any superlatives they want to use, my reservoir is bone dry. 

"There's just not the right superlative that's out there to describe it. I haven't seen a Vegas line yet, but I'll take the +3.5 and take the over." 

This is a Super Bowl that has enough storylines to last two broadcasts, which is part of the fun of the Brady-Mahomes matchup. After broadcasting Super Bowl LIII (13-3 final), this is a matchup Nantz is salivating over. 

"This one is a dream. In some ways it feels like we're due," Nantz said. "We had the fewest points by a winner and loser in our last Super Bowl. We had one play in the entire game that was run inside of the red zone. That was it, the entire game!

"I look at this matchup, that's impossible. That won't happen here. Hold your breath. There will be a highlight coming at you every couple minutes."

Romo understands the significance of this Super Bowl -- calling it "the biggest game Patrick Mahomes will play in the rest of his career." If Mahomes loses -- according to Romo -- he can not catch Brady as the greatest player to ever play the game. 

"This is the only kid that is going to be in the discussion," Romo said. "This is the matchup people will be talking about 25 to 50 years from now. As a football fan, this is as good as it gets. This one is really special."