WHEN ROBERT Covington went undrafted after four productive seasons at Tennessee State, he wasn't sure where his future in basketball might take him. Most assuredly he didn't have in his mind that Rio Grand Valley, Texas, would be his steppingstone to the NBA.

After signing a contract with the Rockets in the summer of 2013, Covington yo-yoed between Houston and the Rio Grand Valley Vipers, of the NBA Development League, for the entire season. He was sent down to the Vipers six times before being waived just before the 2014-15 season began.

He played only seven games, totaling 34 minutes in Houston, so scouts didn't get a read on his NBA game. Instead, he was able to showcase himself in the minor league, where he averaged 23.2 points in 42 games, made 37 percent of his three-point shots and averaged 9.2 rebounds a game.

When he was signed by the 76ers a little more than two weeks after his Houston release, he immediately became the team's best shooter and, eventually, one of it's most capable scorers.

It is just one of the many rags-to-riches stories that come out of the league that many people don't know about. Yes, the Sixers' D-League affiliate, the Delaware 87ers, plays right down I-95 at the Bob Carpenter Center at the University of Delaware, but with six Division I college basketball programs and the Sixers feeding the basketball appetite of Philadelphians, the D-League, now in its 15th season, is an afterthought. Without it, however, the NBA couldn't thrive the way that it has over recent years and the opportunities that are afforded in so many areas of the NBA simply wouldn't be filled as capably as they are.

As Rod Baker, a Sixers scout who coached in the league, said, "Everybody from the players to the coaches to the ticket managers to the game-day ops people are all competing. Everybody is trying to get that call-up. That's what makes it good."

In 2005, then-NBA commissioner David Stern announced a plan to expand the Development League to 15 teams, with the thought to make it a true farm system to the NBA. With the addition of franchises in Chicago, Charlotte and Brooklyn in the 2016-17 season, the NBADL will have 22 teams, each affiliated with an NBA organization.

It has truly become the Triple A version of basketball, with players, coaches, general managers and other workers getting scooped up to the big league. Two current head coaches, Utah's Quin Snyder and Memphis' Dave Joerger, spent time in the Development League, along with 32 assistant coaches now sitting on benches in the NBA.

Like its parent league, the D-League is growing by leaps and bounds, both on and off the court.

"Our No. 1 priority when I came on board was expansion and, ideally, to get each of the NBA teams to having their own D-League affiliate," said Malcolm Turner, president of the NBA Development League since 2014. "We are all tied in together with the NBA. We are housed in NBA headquarters. Part of what we stand for as a league is strategic assets for the NBA system. And there, obviously, is the player development aspect. Last season was a record year for D-League expansion in the NBA. Thirty-eight percent of NBA rosters had players with D-League experience. Thirty-five percent of the playoff rosters had D-League experienced players. There was a record number of D-League players called up - 195 times assigned. General managers and coaches recognize it's a platform to player development.

"An additional example beyond development is, we have the opportunity to use technology, experiment with rules, gather data. We are looking to make a great game better."

An example of that is something the league is trying this year with a coach's challenge. During the fourth quarter of games, a coach is allowed to challenge a call, which then gets looked at on replay before a decision is made. It is something that - if looked upon favorably - could be implemented in the NBA in the not-too-distant future.

"We're a learning lab, a platform," Turner said. "Whether it's technology, strategy or different approaches to the game. That's what we stand for."

As the term one-and-done becomes so familiar with college basketball players now, many are finding it hard once they declare their eligibility for the NBA draft. So many think they are ready for life in the NBA, but very few can actually make the jump. That means either playing overseas or trying to get noticed in the D-League.

Baker, for one, thinks the D-League is the way to go, for both players and others looking to make their way in the NBA.

"It's the only way to do it now," said Baker, who had D-League coaching stints with the Bakersfield (Calif.) Jam and 87ers. "If you look at the new hires that come about, if it's not a former player, it's someone who has gone through the D-League. (Cleveland Cavaliers assistant coach) James Posey has a ring, but he started off on the Canton (Ohio) Charge bench. Now he's coaching LeBron (James) every night. It's really the only way to do it. I really think that the D-League is the second-best league in the world. I mean that. I know what's overseas, and that's great ball. This is better.

"Not everybody can handle being overseas, not handle what that grind is. In the D-League, they understand that grind. They don't appreciate it or want it, but they know this is the next step to their dream."

Covington realized that from the first time he got sent down by the Rockets. He didn't look at it as a demotion, but more as a chance to showcase what he believed to be NBA talents. He won the league's rookie of the year award. He garnered the MVP in the All-Star Game, which was in New Orleans. And when the Rockets let him go on Oct. 27, 2014, the Sixers were there to quickly scoop him up.

"It was always a positive thing for me, going down to the D-League," Covington said. "I know others may not look at it that way, but I did. I thought that, going down there, I could put in the work that I was supposed to and improve my game. Sitting on the bench in Houston didn't do that for me. The Development League gave me a chance to be a big part of a team, to get my confidence back by playing, and playing well, against really good players. Every team has guys who have been in the league or will soon be. I never knew when my opportunity was coming when I was sitting on an NBA bench. Being down in the D-League was a confidence booster and helped me tremendously in getting where I am now."

And there are a lot of Robert Covington-types lingering in the league now, just waiting to get the break he did.

"Think about this. On Covs' team, it was him and (Sixers guard) Isaiah (Canaan) on the same team," Baker said. "They also had the kid now playing in Toronto, James Johnson. Playing for Delaware right now is Russ Smith, a first-team all-America (Louisville) who won a national championship. There are players all throughout the league who just need a break."

With expansion continually happening and the top priority of the league's president, there will be even more opportunity for that in the near future.

cooneyb@phillynews.com

On Twitter: @BobCooney76

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