They are both listed at 6 feet, 5 inches tall and, with genuine admiration, call each other a "beast." In 2012, they had epic seasons on opposite sides of the ball, then suffered a numbers decline last year when their teams failed to make the playoffs.
That didn't stop our 90 evaluators from crowning them ESPN.com's second annual top 100 player #NFLRank champions.
"Whoa," said Johnson from the Lions' training camp in Allen Park, Michigan. "That's pretty cool ... that's pretty cool. It's crazy because there are some great players I view at the top of their game and they are the best. Those are game-changers, so that really means something.
"It's an honor."
Watt responded in much the same manner from Houston.
"Obviously, it's an honor," he said. "I appreciate that. It's humbling when you think of all the good players in the National Football League."
Johnson earned an aggregate score of 9.89 -- the highest of any player -- and Watt's 9.78 was the best for any defender. Watt repeated as No. 1 defender; Johnson was second last year to Green Bay Packers quarterback Aaron Rodgers.
How did Johnson win? Because he was viewed as the clear-cut best wide receiver. Johnson received more 10s than any other player (80 of 90 voters gave him a 10), while the top quarterbacks -- Rodgers, Peyton Manning, Drew Brees and Tom Brady -- split the vote at their position.
In 2012, Johnson caught 122 passes and broke Jerry Rice's single-season record for receiving with 1,964 yards. Last year, battling a variety of ailments, he collected 84 passes for 1,492 yards and 12 touchdowns in 14 games.
Likewise, Watt was incandescent in 2012, recording 81 tackles (39 for loss), a league-high 20.5 sacks and 18 passes defended. Last year, playing for a 2-14 team, he produced 80 tackles and 10.5 sacks.
Which begs the question: Whose gridiron cuisine reigns supreme in the battle between Megatron and Mega-Watt? They'll run through people on the football field but, not surprisingly, neither player wanted to tackle that one.
"No clue," said Johnson, the No. 2 overall pick in the 2007 NFL draft. "I don't make the lists. I'm just a by-product of all that media attention. I leave that to you guys.
"I mean, you want to be the top dog on those lists. Yeah, the guys talk about it in the locker room."
Watt wouldn't speculate, either.
"There's a lot of great players out there," he said. "I can't really say exactly where everybody fits in."
The one thing they agree on? How much fun it would be to play on the other side of the ball. They both relish the idea of doing what the other does. Imagine if the two traded places.
"Yeah," Watt said, "I'd really like to do that. It would be pretty neat to play tight end in this league. I think I could handle that opportunity.
"I played it back in the day, but defensive end has worked out pretty well for me."
At Pewaukee High School in Wisconsin, Watt caught 26 passes for 400 yards and six touchdowns as a senior in 2006. He caught eight for 77 yards a year later at Central Michigan before transferring to the University of Wisconsin and becoming a full-time defender.
"He's pretty good where he is," Johnson said, laughing. "Dude's a beast. Nobody's going to hold him on the line of scrimmage -- as long as he can catch the ball."
Growing up in Georgia, Johnson played cornerback in middle school.
"I didn't get any interceptions," he said, "but I got to hit people, which was cool. Then I got a growth spurt and they moved me to receiver in high school. Special teams was as close as I got to playing defense."
Watt has a better idea.
"Calvin can play wherever he wants," Watt said. "Seriously. He's a really big guy -- and strong. He's a terrific athlete. Maybe some free safety, strong [safety]. I could see him coming off the edge and getting after the passer."
The suggestion made Johnson laugh.
"I would love to get in the three-point [stance] and haul ass and get to the QB. But I think my best position would be free safety."
And then Johnson paused, perhaps weary of all those hypotheticals.
"Time to stop talking about what-ifs," he said. "Time to get back to playing ball."
Amen. Let the games begin.