TUSCALOOSA, Ala. -- Like any parent, Kassna Daniels waited patiently for her son to take his first step. The progression began normally; he sat up, then crawled, then stood. But what happened next was anything but normal: His first step didn't follow; his first step was instead a stride.

"He never walked; he started running at 7 months," Daniels said. "From the time he could stand, he went straight to running."

That's how Calvin Ridley's speed truly made its debut, but for debuts of other sorts, he had much more in store.

In his first game for Coconut Creek (Fla.) Monarch High, he broke a kickoff return for a touchdown. Two years later, as a true freshman at Alabama, he stepped into Amari Cooper's massive shoes and became the Crimson Tide's new WR1.

Ridley's blazing speed has been a constant marker on his football accomplishments, and it leaves an impression wherever he goes. To wit, consider the way former Alabama assistant Mario Cristobal, ex-Tide quarterback Jake Coker, and Florida Fire 7-on-7 coach Dennis Marroquin answered the same question in separate interviews: What single word would you use to describe Ridley's game?

"Explosive," they all answered.

Ridley's path to the cusp of an NFL career hasn't come easily; he's overcome a difficult childhood and, at one point, even football was taken away from him. Now, he's approaching yet another debut, this time as an NFL rookie, and scouts expect him to be among the true prizes at his position.

And if history is any indication, that debut will be explosive, too.

Tales of Ridley's speed are endless, but Parker Barrineau might have the best story of them all.

Players on the school's vaunted defense, loaded with draft prospects every year, have been known to chide Alabama offensive coordinators who can't move the ball on them in practice. Lane Kiffin, whose ego as a play-caller and offensive mind has been well-documented, didn't always appreciate it.

But Ridley was always his best answer.

"If the defense was pounding on us for too long, Kiffin would get pissed," said Barrineau, a reserve wide receiver for Alabama from 2012 to 2015. "(Cornerback) Tony Brown or someone else on defense would talk some trash to him, like, 'Kiffin, you can't even get a first down on us.' Whenever Lane had had enough, he'd grab Calvin and send in a go route. And Calvin would burn them deep almost every time. That was his best way to make the defense stop talking so much."

Ridley hasn't seen his biological father since age 7, when Colin Ridley was deported to Guyana. Soon after, he and his three younger brothers -- Riley, Clamont and Clayton -- entered foster care while their mother was dealing with what she describes as "personal problems," a subject she chooses not to elaborate too much on.

"I had some difficulty in my life, and I had to get myself together to get my four boys back," said Daniels, a former prep track star in Ft. Lauderdale who ran sprints and intermediate distances in the early '80s. "It took me three years, but with the help of God, I got them back."

In the same foster home with the Ridley brothers were another set of four siblings that included Shawn Burgess, whom Calvin formed an instant friendship. Burgess, who was later legally adopted by a man named Tom Becker and now goes by the name Shawn Burgess-Becker, shared his home with Ridley for his final two years of high school at Monarch, where the football team included several foster-care kids.

"In the beginning, it wasn't easy, but it got better," Ridley said. "We learned to play football together from a young age, and we stayed together."

Fortunately, the circumstances didn't adversely affect the relationship between Ridley and his mother. To the contrary, it's a bond Calvin cherishes. "She means everything to me," he said. "She's a strong woman."

Ridley and Burgess-Becker were a package deal for Alabama, as both were part of the Crimson Tide's 2015 signing class. Much has changed since then, however.

Ridley was recruited to Alabama by Cristobal, who is now at Oregon. His first position coach, Napier, is now at Arizona State, and his offensive coordinator was Kiffin, now the head coach at Florida Atlantic. Burgess-Becker, Ridley's best friend, transferred to Central Florida.

But for someone who went through foster care and later attended three different high schools, Ridley was well-prepared to deal with their absences.

"I'm kind of used to people coming and going," he said.

One of the constants for Ridley at Alabama has been Saban, who like with so many of his players has served as a father figure to the wide receiver. Daniels couldn't be more thankful.

"Nick Saban has grown my son into the man he is," she said. "The difference coach Saban has made for Calvin personally isn't a little bit. It's a lot."

Ridley has a secret about his 2015 season at Alabama, when his 1,045 receiving yards broke a Crimson Tide freshman record set by Cooper. Despite that instant success, for a significant portion of the season his confidence was largely in the hands of Barrineau. A year earlier, Kiffin and Napier gave the reserve walk-on the responsibility of delivering hand signals to the offense from the sideline. But there's more to that story.

"I don't know if anyone knows this, but Parker was my personal signaler," Ridley said, grinning. "You had 10 guys looking at one thing, and here's me looking at something else. The playbook was so big, so much bigger than high school, it was all I could do to just get lined up right. I didn't always know what I was supposed to do."

So what exactly was Barrineau's role in the most prolific freshman season an Alabama receiver has ever had?

"We had general hand signals for everyone else that were just concepts. You tell the right side of the field what to do with one hand, the left side what to do with the other. That's all the veterans needed, and they knew what route to run," Barrineau said. "After I would signal that, I knew Calvin would still be looking at me. I'd give him an individual signal for his route. That just gave him the full confidence to know, 'I'm running a post, I don't have to second guess it, and I'm going full speed.' "

A full-speed Ridley singed Georgia CB Aaron Davis in an October 2015 game that proved to be Ridley's breakout performance. Barrineau signaled a go route -- Ridley's favorite -- and 45 yards later, Ridley had blown past Davis for his first SEC touchdown in what would be his first 100-yard game. After that, the Ridley-Barrineau relationship changed.

"After the Georgia game, I felt like I didn't need that (personalized hand signals) anymore," Ridley said. "I told Parker I could just look at the same signals everyone else was looking at."

Thereafter, Coker made Ridley his true big-play target. The two were a complementary pair. Coker was a tall, sturdy pocket passer who lacked touch at times but had a big arm and excelled throwing the deep ball; Ridley was a frighteningly fast vertical threat who could take the top off a defense and give Coker a chance to do what he did best.

"He would run these bender routes where he'd have a hash read and he'd just break it off and get vertical and nobody could stay with him," Coker said. "He accelerates so fast out of the break, he's unguardable. His speed is one thing, but when he makes a cut, that's where he gets separation, because he doesn't lose a step. He and Amari both have that."

For his Alabama career, Ridley finished second in receptions with 224, four short of Cooper's record 228. He finished third all-time in receiving yards with 2,781, behind Cooper (3,463) and D.J. Hall (2,781), and just ahead of Julio Jones (2,653).

Had Ridley been a high school recruit a couple decades earlier, back when a player's senior season carried more importance to college coaches, he might not have landed at a top program like Alabama.

Today, summer camp performances drive scholarship offers more than senior-year game tapes, and Ridley was already regarded as the No. 1 receiver in the nation for the 2015 recruiting class long before his senior season began. That proved to be fortunate, because his final high school season was over early.

Florida High School Athletic Association bylaw 9.6.1 states that players can be no older than 19 years and nine months to participate. Ridley reached 19-9 in September 2014 and "aged out" just three games into the schedule.

On the final play of a 48-0 road win over Sunrise Piper, the last snap of Ridley's prep career, he took a backside post 40 yards for a touchdown. It was a strange scene as some in the Piper home crowd, unaware that they'd just witnessed the end of a storied high school career, didn't take kindly to a touchdown pass being tacked onto the end of a blowout. Others knew Ridley was finished, however, and as the entire Monarch squad congratulated Ridley, some Piper players and even a few fans gave him an ovation. Monarch coach Calvin Davis shed tears.

It was a fitting way to bookend a brief but brilliant run. A little more than a year earlier, in his first game for Monarch, Ridley took a kickoff return for a touchdown. In his final game, he caught seven passes for 186 yards and the final-play touchdown.

Davis tapped Ridley to help coach receivers for the remainder of the season. For a player who wanted to remain as involved with the program as possible, it was the ideal way to make the best of a bad situation. Calvin's younger brother Riley, now a wideout at Georgia, and Jerry Jeudy, a promising Alabama freshman who could eventually step into Ridley's shoes as the Crimson Tide's WR1, became his pupils.

"I just invested myself and my time in those guys," Ridley said. "I knew I still had more football ahead of me."

The previous year, knowing the ineligibility was forthcoming, Davis and Tom Becker -- the man who adopted Shawn Burgess and Ridley's mentor -- began building a case for appeal they hoped would allow Ridley to complete his senior season. Monarch's athletic director didn't believe the appeals case was strong enough to be filed, however, resulting in a heated argument with Becker.

"Calvin looked at me and said, 'Don't worry about it. I can stand on the sideline and be part of the team anyway,' " Becker said. "That floored me. I thought, 'This is maturity here. This is awesome.' "

Long before Ridley's speed forged respect from college coaches, NFL scouts and draft analysts, it gained a more subtle notoriety with those from whom teenagers crave respect most: other teenagers.

On a sunny day in Ft. Lauderdale in 2014, he got some. That's where the Strong Arm Elite 7-on-7 tournament was held, and the Florida Fire roster was buzzing, not from the scheduled games but about the sideshow: a 40-yard footrace featuring eight of the event's swiftest players, two from each of four teams. On a roster laden with future Division I players -- FSU's Da'Vante Phillips and Michigan's Devin Bush among them -- it was Ridley and Antonio Howard who were chosen to represent the Fire.

Players made Howard the presumptive favorite. Now a defensive back at Texas A&M, Howard had been clocked in the 4.3s and was generally considered the Fire's fastest. But it was Ridley who broke the tape.

"I think we actually raced 60 yards, and that was fine with me, because I get faster as I go," Ridley said. "The guy is very fast, but on that day, I got him."

And so grew his reputation.

"All the kids were like, 'Whoa,' " said Fire coach Dennis Marroquin. "They knew Calvin was fast, but that was something they didn't expect."

Fire opponents couldn't say the same. They knew all about the Monarch High star who would ultimately become the No. 1-ranked wide receiver in America. Marroquin called a go route for Ridley on the first play of every game, a signal to the opposing defense that the deep ball would have to be respected.

"You couldn't overthrow the guy," said South Florida star QB Quinton Flowers, who quarterbacked the Fire for the first of Ridley's two years with the club. "When we first started, I was underthrowing him. Once I understood how fast he was, I realized how quickly I had to let it go and get it downfield on the go (route). You can let it hang a little so he can read it and get under it, but you'd better get it out quick. You hold it, and he'll have to stop and wait on it."

In an early November matchup in Tuscaloosa last fall, Ridley's speed got one of its stiffest tests in the form of LSU cornerback Donte Jackson, who was widely regarded as the fastest player in college football last season. Ridley led Alabama with three receptions for 61 yards in a 24-10 victory.

Turns out, the test was Jackson's.

After all, he was covering a guy who ran before he even walked.