Mavs rookie Dennis Smith Jr. signs with Under Armour

Dennis Smith Jr. lights up summer league (0:58)

The Mavs rookie and No. 9 overall pick draws comparisons to a young Derrick Rose, Steve Francis, and Penny Hardaway. (0:58)

The most marketable NBA players are typically guards. Players with the ball in their hands -- explosive attackers with an endless flair to their game. As kids look up to and spend endless hours in front-yard hoops emulating their every move, brands are left constantly looking for the next great athletes who can translate into equally great endorsers.

Dennis Smith Jr. checks all of those boxes, leading Under Armour to sign the Dallas Mavericks rookie point guard and No. 9 overall 2017 draft pick to a three-year footwear and apparel endorsement deal worth as much as $2 million per year with incentives, according to sources. The brand plans to incorporate him immediately as one of its key featured basketball players right out the gate.

"I am definitely excited to be a part of team Under Armour as I get ready to go into [training] camp for my rookie year," Smith Jr. said. "Under Armour is an explosive brand in basketball right now, and I'm excited to join Stephen [Curry] and Seth [Curry] and the team at UA in making our mark together."

Unlike most incoming rookies this summer, Smith decided to wait until well after the NBA draft to sign his sneaker deal. The majority of the players selected among the top 10 picks -- save for Lonzo Ball's unique Big Baller Brand venture -- each signed their endorsement deals during the month of June.

As Smith was receiving offers just south of a million dollars per year, his inherent confidence in his own abilities and potential led him to bet on himself. He decided to play throughout the Las Vegas Summer League first, while switching between sneakers from several brands and eventually landed a higher offer from Under Armour.

In just his fourth game, the 6-foot-3 Smith brought the ball past half court and quickly careened along the right wing, using a sudden between-the-legs dribble to blow by his defender. With two more dribbles left, he headed straight to the key through a wide-open lane, taking off beyond the restricted circle and unleashing on the rim, as his teammates all simultaneously rose from the Mavs bench. It was the clear-cut highlight of Summer League, sending real-time social media into a frenzy. No one even cared that he actually missed the dunk.

Kris Stone, Under Armour's pro basketball sports marketing director with a final say on which NBA players the brand signs, can vividly recall the first time he saw Dennis Smith Jr. in person. It was during the summer of 2015, as Smith was among a group of 20 elite point guards from around the country invited to Stephen Curry's SC30 Select Camp.

"The first time that I saw Dennis Smith at camp was when Stephen ran out of the gym after he tried to dunk on somebody," Stone said with a laugh. "Dennis got so high -- his elbow was at the rim. It was unbelievable. That was my first time experiencing what Dennis can bring to the table in terms of explosiveness. The reaction that Stephen had was ridiculous. Stephen was coming off of an MVP season and an NBA championship, and here he is, watching a high school kid own the moment and respecting it."

Smith worked out all that week with Curry, taking turns on shooting drills from all over the court, gleaning his knowledge of the game on how to read varying pick-and-roll coverages, and even mimicking his tennis-ball, hand-eye coordination drills.

He went on to be crowned the one-on-one champion of that summer's SC30 Camp, and there has been a foundation of the relationship between both Under Armour, Curry and Smith ever since. Hanif Hill, a senior adviser to Under Armour's pro basketball sports marketing group, was instrumental in managing the relationship along the way.

As his game continued to progress, Smith bounced back from an injury that saw him sit out his entire senior season at Trinity Christian School. Smith was named ACC Freshman of the Year during his lone season at NC State, showcasing the explosiveness and raw scoring ability that first put him on the map as a prep phenom. From a sneaker standpoint, he wore over 10 different pairs throughout the season, showcasing his interest in standing out in loud or flashy models.

With representatives from interested brands all watching closely, Smith went on to average 17.3 points, 4.8 rebounds, 4.2 assists and 2.2 steals per game during the Mavericks' run in Vegas, landing him on the All-NBA Summer League first team. His play has drawn comparisons to early seasons of both Russell Westbrook and Derrick Rose.

"He looked like a pro, and he carried himself with humility," Stone said. "He played with an aggressiveness and a chip on his shoulder but wasn't trying to embarrass somebody after he made a shot by pumping his chest. He just went about his business. For a young basketball player, he looked mature."

As often happens throughout the industry, given that there are millions of dollars potentially on the line and marketing commitments to be made, brands will do their research on not just a player's ability on the floor, but his or her character, demeanor and personality off it. In Smith's case, one of his new teammates, Under Armour endorser Seth Curry, vouched for him after they got to know each other at the Mavericks practice facility earlier in the summer.

"Seth was able to spend some time with him, and Seth was telling me how good of a person he is," Stone said. "Coming from Seth, and understanding what the Curry family is all about, that really resonated with us."

As Dennis Smith Jr. prepares to embark on his rookie season, he'll be among a few select players leading the new Drive 4 team shoe. During Summer League, Smith wore the sneaker in a custom-made edition inspired by some of his favorite TV shows of the '90s. Under Armour just so happens to have one of their flagship "Brand House" stores in Dallas, where they'll look to feature Smith in both in-store marketing, as well as launch exclusive products.

More than anything, the two are looking to build on their underdog mindset together as Under Armour continues to find its way in the footwear business and Smith looks to make his mark in the league.

"If you look at all the other brands we're competing with, we're not even a quarter of their size and we're the underdog. Dennis was overlooked in the draft. We're both still trying to climb a mountain," Stone said. "He has a lot of hunger to be on top. Hopefully, we can really partner with him and not just have some transactional relationship. We're looking to have a real partnership with him and help him get to those places that he wants to go."