The odds of making it to the NFL are long. Just nine high school football players out of every 10,000 will get drafted by a pro team. Shaquem Griffin didn't just beat those odds, he made history. This fall, Griffin became the first one-handed player in the modern era of the NFL. You may have heard some of his story. But what you may not know is how Shaquem Griffin ended up playing on the same NFL team as his twin brother, Shaquill. It wasn't by chance. The brothers made a secret pact as children. A promise no one would have blamed them for breaking.

There's nothing complicated about Shaquem Griffin's approach to football. Number 49 zeros in on his opponents with the speed and impact of a tomahawk missile.

Shaquem and Shaquill Griffin CBS News

Spend some time looking at his college highlights and you can see how the absence of a left hand forced Griffin to develop an ideal tackling technique.

He targets the ball carrier's hip and drives his shoulder in as he whips his arms around him to make the tackle. Once his sights are set. There is no escape.

Sharyn Alfonsi: People can't believe how good you are with one hand. How good would you be with two hands?

Shaquem Griffin: I probably wouldn't be that good.

Sharyn Alfonsi: Why?

Shaquem Griffin: I thought about it. I was like, "If I had two hands I don't think I'd be good as I am now." I think me having one hand made me work even harder than many other people.

Sharyn Alfonsi: What do you mean by that?

Shaquem Griffin: I feel like if you only put one hour in, I probably need to put in an hour and 30, or I need to put in two hours.

Shaquem Griffin plays linebacker and on special teams for the Seattle Seahawks. His teammate in Seattle, and in life, is his identical twin Shaquill.

They can be hard to tell apart.

Shaquem is on the left of your screen and that's Shaquill on the right. He is one of the best cornerbacks in the league.

Shaquem Griffin: As a brother, he's very protective and he takes his being a big brother role very seriously.

Sharyn Alfonsi: But how much of a big brother is he? You're twins.

Shaquem Griffin: 60 seconds. Be he makes it feel like its been years since he's been born. he does good at his job I guess because he thinks it's a job being a big brother.

Sharyn Alfonsi: Do you think it's a job being a big brother?

Shaquill Griffin: Yes, well, if you're his big brother. It's definitely a job.

We first met the twins at a family reunion in Atlanta, where they were sporting matching t-shirts and smiles.

Tangie Griffin

But back at the home they share in Seattle, they bicker like only brothers can. It took all of a five minutes before a friendly ping pong match became an argument over the score.

Shaquem Griffin: So what I got?

Shaquill Griffin: I got 8-3. I got one more serve.

Shaquem Griffin: 8-3? No it's my serve. It's 8-4. I knew you would try to lie. Give me the ball.

Shaquill Griffin: You said you got five.

Shaquem Griffin: Yeah, I thought you had seven.

This constant competition has been going on since they were toddlers.

Shaquill Griffin: You know, I'll give you an extra point.

Shaquem Griffin: So it's on me.

Shaquill Griffin: I got points to spare.

Shaquem Griffin: That's five.

Shaquill Griffin: I was just te-- You see? You see what I go through? You see what I go through?

Sharyn Alfonsi:: What were they like as two-year olds?

Terry Griffin: Whooey. One'd go that way. One'd go that way.

Terry Griffin is their dad. Tangie is their mom. When the twins weren't pounding on each other they were wrecking their house in St. Petersburg, Florida.

Terry and Tangie Griffin CBS News

Terry Griffin: Sports was more or less s-- something to take some of that energy.

Sharyn Alfonsi: You needed to run them out.

Terry Griffin: I needed to run them. I needed to run them. And they were so excited. They were like, "Dad, can I--" "Run, boy. Run, (LAUGHTER) run, run, run. Matter of fact, you can run some. Give me a call when you're finished." (LAUGHTER)

Nothing slowed Shaquem down, including the birth defect that deformed his left hand. During pregnancy, small strands of tissue constricted his fingers. It's called amniotic band syndrome. The undeveloped hand caused him pain until it was amputated when he was four.

Sharyn Alfonsi: Did you ever think about getting him a prosthetic?

Tangie Griffin: I thought about it. And then I said, "You know what? I'm-- I'm not gonna do it."

Sharyn Alfonsi: Why?

Tangie Griffin: Because he started working and he didn't need it. You know, he was able to button up his shirt, and button up his pants, tie his shoes.

Sharyn Alfonsi: How did you teach him, and I guess you probably taught him, how did you teach him to catch a ball without a hand?

Terry Griffin: When you get hit in the face about five, six, seven, times, (LAUGH) you-- he used to, like--

Sharyn Alfonsi: You're going to figure it out real quick.

Terry Griffin: Yeah, you'll-- you'll start catching. He wanted it. You have-- you gotta want it.

"We promised each other. Nothing will stop us. Nobody will interfere in what we want. And that's to be together."

But the Griffins told us not everyone wanted Shaquem on the field. Some opposing coaches didn't want a kid with one hand out there and told their players to target him. And then there were the looks.

Tangie Griffin: You have adults, they'll just stare instead of asking. And then the kids will ask, "Well, what happened to your hand?" "Oh my daddy, we went fishing and a shark jumped up and bit my (LAUGH) hand off." So every time, he would always make a joke out of it. And that's just growing up. But Shaquill wasn't okay with it. Shaquill didn't think it was something to be teased about. He didn't even like the fact that when Shaquem would joke about it. And Shaquill protects him right now. He's very protective of his brother.

Sharyn Alfonsi: Shaquem is now 6'1", 230-some pounds. Does he need protecting?

Tangie Griffin: He doesn't need protecting, but Quill doesn't feel like he doesn't.

Sharyn Alfonsi: Still.

Tangie Griffin: Still.

By the time they were teenagers, Terry Griffin was designing contraptions to allow his one-handed son to do the same demanding weightlifting as his twin brother. This one was called "the book."

Shaquem Griffin: It's literally like-- a block of wood, a book, and then a sock over it.

Shaquill Griffin: On top of it.

Shaquem Griffin: And then, like, a small block on top of the sock-- where it kinda-- kinda clips or hooks to the bar. My brother can hold-- hold it and guide it.

Lifting was followed by daily backyard drills dreamt up, and directed, by their father.

Sharyn Alfonsi: What did the neighbors think was going on at the Griffin (LAUGH) house?

Shaquem Griffin: Like we're getting ready for war. There was so much stuff (LAUGH) going around. You got us in the backyard jumping over bricks. And--

Shaquill Griffin: A lotta yelling.

Shaquem Griffin: A lotta (LAUGHTER) yelling. And oh my goodness. The dog was screaming.

Shaquill Griffin: They knew we were training for something serious.

Shaquem Griffin: Yeah!

Shaquem Griffin with correspondent Sharyn Alfonsi CBS News

The twins became high school football stars: Shaquill with finesse, Shaquem with the speed of a running back and a ferociousness that earned him the nickname "beast."

Terry Griffin: Quem would tackle you on top of the Gatorade and give you a cup.

But when college scouts came calling, they only offered a football scholarship to Shaquill. What those coaches didn't know is that Shaquill wasn't going anywhere without Shaquem. The twins had made a pact to stay together.

Sharyn Alfonsi: When did this happen? How old were you?

Shaquill Griffin: We probably had to be, like, eight.

Sharyn Alfonsi: Okay, but eight-year-olds say a lot of things and don't mean it. That-- that made perfect sense when you were eight years old. But the offers start coming in. And what did-- you wanted to go to Miami. Is that right?

Shaquill Griffin: Yeah.

Sharyn Alfonsi: That was the dream?

Shaquill Griffin: Uh-huh.

Sharyn Alfonsi: And?

Shaquill Griffin: I remember doing the interview. And I was talking about, you know, "Just don't offer me. If you don't offer my brother, don't offer me. Because I'm not leaving him."

Sharyn Alfonsi: Why wouldn't you leave without him?

Shaquill Griffin: I don't know. I think I wouldn't be the same if I went alone.

Tangie Griffin: And he was offered Florida State, Miami--

Terry Griffin: LSU.

Tangie Griffin: LSU. The-- the top schools in the country. And Shaquem was like, "Look, man. Go ahead. I'll be all right." And Quill said, "No, we made a pact. We promised each other. Nothing will stop us. Nobody will interfere in what we want. And that's to be together."

It was the University of Central Florida that gave the Griffins what they wanted: twin scholarships. But while Shaquill became a star, Shaquem was stuck on the bench and told by coaches he'd only be a shadow of his brother.

Sharyn Alfonsi: How close were you to quitting?

Shaquem Griffin: I was really close.

Shaquill Griffin: You get to a point where he said, "I was leavin'," and I was gonna leave too. And then I think he ended up staying because he knew how much it would affect me. I said, "If you leave then you's just breaking everything we promised to each other."

It took a coaching change to give Shaquem a fresh start. He spent his last two years in college playing like a man possessed, determined to destroy doubt or anything else in his path. His stats were phenomenal: 18 sacks, 195 tackles and this fumble recovery he scooped up for a touchdown. The one-handed player also made three interceptions.

Sharyn Alfonsi: Show me how you do it.

Shaquem Griffin: I mean, it's no, like, science to it. Catch it, got it in, and put pressure against it. Because obviously when you catch a ball you're going to put pressure with this hand, and then with this one I gotta make sure I compensate it. So I put pressure against it and make sure I grab it, squeeze, hold on tight to it.

Sharyn Alfonsi: And bring it on in.

Shaquem Griffin: Bring it on in.

"Whatever there was that might have held him back, he overcame it in some other way."

Despite being named the defensive player of the year in his conference, Shaquem Griffin was not invited to the NFL combine, a showcase for players looking to go to the pros. Shaquill was furious. He had graduated a year earlier and was a star rookie on the Seahawks.

Shaquill Griffin: I feel like everything he accomplished, if he did it with two hands, he would have gotten invited to the combine first, he probably would have been a first-round pick.

Sharyn Alfonsi: If he had two hands.

Shaquill Griffin: Every-- yeah, every box that you're supposed to check off that you want out an athlete, he did that.

Shaquill was determined to honor their pact. He went to work publically, he demanded his brother get a chance. Privately he lobbied his coaches in Seattle. The NFL recognized a good story when it saw one and invited Shaquem to the combine, where the strength, agility and speed he first developed in his backyard would face its most important test.

Shaquem Griffin: Once I got to that line, I thought about everything I-- that it took for me to even get there. From the doubt, to the negativity, to the coaches saying I wasn't going to be nothing. This is what gonna make your name right now.

He blew the doors off the place, the fastest 40-yard dash ever for a linebacker at the tryout. And the exact same time his brother ran a year earlier.

Suddenly there was talk Shaquem Griffin would be selected by an NFL team as soon as the third round of the draft, but that came and went.

Shaquem Griffin: People don't wanna take a chance. And I just feel like that's what it was, it's like that in every single level I've been in, from little league to high school and college.

Sharyn Alfonsi: How often do people underestimate you?

Shaquem Griffin: I get underestimated every single day.

Seattle Seahawks head coach Pete Carroll CBS News

By the fifth round of the draft the family had retreated to a hotel. That's when the call finally came.

Tangie Griffin: So he gets up and goes to the bathroom. Soon as he went to the bathroom, phone started ringing. Shaquill looked down at the phone and he recognized the area code. And he jumped up. He grabbed the phone, jumped over some of my grandkids, and busted the door. He was like, "I'm using the bathroom." He said, "I don't care. I know this area code. Answer this phone!"

It was Seattle coach Pete Carroll with news that Shaquem Griffin would join Shaquill on the Seahawks.

Pete Carroll: Shaq – you ok?

Shaquem Griffin: I can't breathe right now, I'm not going to lie to you.

Pete Carroll: He still can't breathe.

Shaquem Griffin: Oh my god.

Pete Carroll: This is a great moment--

Shaquem Griffin: Thank you so much.

Pete Carroll: --and we are really excited about it and we're expecting you to come in here and bust ass now, you know that, right?

Shaquem Griffin: Yes, sir. I'm going to give everything I got.

Pete Carroll: Congrats to your brother too and your family. I know everybody's really excited about this.

Just watch this moment. Once again, nothing could come between the Griffin brothers.

Sharyn Alfonsi: You've done this a long time. If anybody had said to you, you're going to draft a guy and he's got one hand. Would you have believed it?

Pete Carroll: No, I would not-- I would not have been able to imagine that. We studied him-- as hard as you could study a guy, we found that whatever there was that might have held him back, he overcame it in some other way.

Shaquem Griffin has played in every game. Mostly on kick returns, but he is bulking up and hellbent on earning more game time. It's a page right out of the Griffin brothers playbook.

Sharyn Alfonsi: When will you say, "I've been successful?"

Shaquem Griffin: To the point where, you know – it's not about me having one hand, it's about me being a great football player. Don't matter if I am playing on special teams, don't matter if I am playing linebacker, I want to be the best at what I am doing.

Sharyn Alfonsi: Not being known as the guy with one hand. You wanna be known as the guy who--

Shaquem Griffin: Yeah, three, four or five-time Pro Bowler, guy who-- the guy who's known for just having a nose for the ball. Like, that's the guy I wanna be.

Produced by Guy Campanile and Lucy Hatcher. Associate producer, Cristina Gallotto.