The tennis balls did it. If you want to know how the Gronkowskis became this year's first family of football -- if you want to know why New England Patriots tight end Rob Gronkowski is the most valuable fantasy football player in the world -- look no further than the tennis balls.

When Gordy Gronkowski's five boys were little, he used to line them up in the backyard and chuck tennis balls at them. Hard. At first, he knew, the boys would be scared. But to be good at sports, you can't be afraid of the ball. And so the balls would come, and the boys would have to catch them. Eventually, they did.

Gordy started this when the boys were 4 years old.

The boys got older. They got wiser. Their hands got softer and their skin got thicker.

So Gordy started hitting the balls at them. With a racquet.

He switched it up sometimes, hitting the balls way up into the air. Gordy wanted his five kids ready -- anytime, all the time. He wanted them to be mentally tough but quick.

"I started 'em on skates at 5 or 6 years," Gordy says. "They all could have played in the NHL."

Are you going to tell Gordy Gronkowski he's crazy? This is a man who has raised three boys to not only college football scholarships, but NFL careers. Rob's with the Pats, Chris is a fullback with the Colts, and Dan is a tight end for the Browns., with a little help from a Yale student, determined the chances of having three kids in the NFL at the same time are 1 in 31 million.

So it was the tennis balls. What else would explain three boys in the NFL? And don't think Gordy got lucky, either. The best athlete in the litter isn't Chris or Dan.

It isn't even Rob.


Maybe it's not the tennis balls. Maybe it's the genes.

"My brother's a big guy," says Gordy, speaking a mile a minute, with that great upstate New York accent. "My father was 6-3. Mom was 5-10. My brother, Glenn, was 6-8."

Gordy's great-grandfather, Ignatius, was an Olympic cyclist in the 1924 Games in Paris. His father was a top athlete, too. And Gordy played football at Syracuse where he blocked for Joe Morris, the school's all-time leading rusher. You see the pattern.

But as we all know, big doesn't always mean athletic. It can also mean awkward and soft. But neither of those traits is in the Gronkowski gene pool.

No, Rob was always tough. Disturbingly tough, in fact. "Robby and Chris -- the battles they used to have," Gordy says. "Robby loved pain. They used to beat on the kid and he would come back for more."

Gordy tells a story of how Chris would be napping and Rob would sneak up on him and "smack him in the face." Then, naturally, Chris would wake up and, like a sleeping bear, attack the threat. It got to the point where Gordy would put all the boys in a room with a bunch of pillows and tell them to go to town until they tired themselves out.

But that took quite a while. "No one would quit," laughs Gordy.


So maybe it's not the genes. Maybe it's the attitude.

The Gronkowskis aren't thugs. And they aren't spoiled, either. Gordy had sports success in his blood, but he also knew deep frustration. He loved baseball and excelled at it, but he blew out his arm. He traveled cross-country to California to try to get a scholarship somewhere but failed everywhere, finally getting a shot way back East at Syracuse because of a letter-writing campaign. Gordy's oldest, Gordie, Jr., never got recruited and went to the University of Jacksonville (also after a letter-writing campaign). He got drafted by the Los Angeles Angels but had to have back surgery. Rob had surgery too -- so serious that he very nearly retired and collected a $4 million insurance policy set up by his dad. He refused, taking a huge financial chance.

Follow us on Facebook and Twitter to read them first!

"My biggest thing was to get 'em educated and get 'em all scholarships," says Gordy. "I thought maybe one of 'em would go pro."

The Mannings seemed predestined for greatness; not the Gronks.

Yes, you have the story from this year of Rob hanging out with a porn star. He "likes to live on the edge," says Gordy. But Rob is not basking in the glow of the NFL. He called his dad last week and said, "One thing I hate is when they say somebody's better than me." That comes from childhood, and his parents telling him that somebody is getting ready to be better than him.

"Don't come to me and tell me you want something if you're playing your Nintendo," Gordy told his boys. "They will catch you unless you stay ahead of the game."

The family basement is where all the hard work happened -- for all five boys. That's where they went to work hard and get better. "When you don't want to go down in the basement," Gordy used to say, "think of what all those people are saying about you." That usually did it. The basement wasn't a dungeon; Gordy wanted his boys to choose rather than be forced. But they all wanted to excel as much as their dad did.

"I don't think any of them went three days without working out," Gordy says, "since eighth grade."

And if you look at the progression of the boys, oldest to youngest, they all got better from watching the next oldest brother work. Gordie, Jr. was the slowest, running a 5.6 40 before developing enough speed to get a shot in pro baseball. Chris and Dan were next -- both making the NFL. Rob is the second-youngest, and the standout at this point. But Gordy says the best athlete of all is the one you haven't seen yet -- Glenn.

"My youngest guy," Dad says, "that is my best all-around athlete. He can play any single sport and be in the top 5 percent. He’s 6-3. He's the fastest one."

Glenn is going to Kansas State to play football. He grayshirted this semester. His dad wanted him to put on some weight. He's running a 4.6 40 now. At a (relatively) diminutive 6-3, Glenn might be more Wes Welker than Rob Gronkowski. We'll all find out.

But during this Christmas weekend, Gordy's feelings are bittersweet. On the one hand, he's getting 75 calls a day (his estimate) from well-wishers. He gets to watch his "guy" catch passes from Tom Brady. "It's crazy," he says. "It's surreal. Every time I turn something on now, he's on it. Listening to what they say ... I created this kid! He's gone way farther than I dreamed in a million years."

But on the other hand, this will be his last Christmas with any of his boys in the house. Gordy and the boys' mom, Diane, are divorced, and although he gives her all kinds of praise for his children's success -- she deserves at least half the credit, right? -- he's going to be alone starting January 15, when Glenn leaves. The basement will be quiet. The racquet will be put away.

"I'm probably going to be lost when he goes," Gordy says.

Maybe it's not the tennis balls. Maybe it's not the genes. Maybe it's not the attitude.

Maybe it's all of the above.

And maybe, for all those reasons, it's dad.