FRISCO, Texas -- It's an hour before the Dallas Mavericks are to play the Denver Nuggets on April 11, 2017. On the practice court inside the American Airlines Center, two teammates are having a 3-point shooting contest.

On this night, Tony Romo and Dirk Nowitzki are those teammates.

"Dirk said, 'We've got to warm up -- 3-point contest,'" the former Dallas Cowboys quarterback remembered. "I'm thinking, 'I'm a pretty good 3-point shooter. Let's do this. I got a chance. It's the only thing I can do well. I make a few and sure enough, I have a little lead. Dirk's like, 'All right, I'm down three. There's four balls left.' He kind of looks at me and smiles."

The first shot goes in. Then the second. Then the third.

"He hits the fourth one and I swear he gave me the Michael Jordan shrug from the NBA Finals, as if he's sorry," Romo said. "He said, 'I was thinking about letting you win, but decided not to.'"

Nowitzki is expected to play the final home game of his storied 21-year career against the Phoenix Suns on Tuesday (8:30 p.m. ET).

Along with shooting hoops with Romo, here are more key connections between Nowitzki and the Cowboys:

Romo: Dirk warned of career ebbs, flows

As a senior at Burlington High School in Wiscsonsin, Romo was an All-Racine County basketball pick along with Caron Butler, who would go on to be one of Nowitzki's teammates in Dallas. Romo had the chance to play college basketball but opted for football. His love of basketball never waned, playing in serious games across Dallas during his time as Cowboys quarterback.

After announcing his retirement from the NFL, the Mavericks wanted to honor Romo and decided to make him a player for a day. He went through meetings and practice as well as the pregame shootaround and warm-ups. He even sat in for the team photo. League rules prevented Romo from getting in the game, but that did not stop Nowitzki from playfully yanking off the warm-up to try to get him in for a minute.

"I can remember going through tough stretches early in my career," Romo said, "and Dirk would not only send me a text, but we saw each other at dinner one night and he made a point of telling me, 'You're going to have ebbs and flows in your career. Sometimes it's going to go great. Sometimes not. There's going to be some teams that will be better and some not as good, but just keep working.' And he was dead right."

Garrett: The 7-footer is a focal point

Cowboys coach Jason Garrett was quarterback Troy Aikman's backup when Nowitzki arrived in Dallas in 1998. He remembered going to Reunion Arena and seeing the gangly German play.

"I enjoyed seeing him and Steve Nash play," Garrett said. "Two guys that just played the game at such a high level and just real professional. Smart players. Seeing those guys playing individually but then playing together was really special and fun to follow."

Garrett left for the New York Giants as a free agent after Nowitzki's second season and did not return year-round to Dallas until he was named the Cowboys' offensive coordinator in 2007.

"He's so skilled, and literally being 7-feet tall," Garrett said. "We've seen skillful players around the basket who were 6-11, 7 feet, north of 7 feet, but he played away from the basket, around the 3-point line."

Garrett remembers reading about the hours Nowitzki would put in with Holger Geschwindner, his personal coach, on his balance while shooting.

"In football you call it 'funny body throws,'" Garrett said. "He'd make so many funny body shots, but if you'd look at him, he was in complete control and balance."

As a coach, Garrett has developed a tight relationship with Mavericks coach Rick Carlisle over the years, and they have spent hours discussing Nowitzki's greatness, while comparing notes on how to get the best out of players of any skill set.

"He's one of those players for me when I go to a game, you just watch him," said Garrett, who attended the Mavs' home game last Friday with his wife, Brill. "My eyes are drawn to watch him do everything. You watch him run down the court, set up, create his shot, get himself in balance. Then coming back the other way defensively, communicating. He's just one of those guys you watch through the game just beyond when the ball is in his hands. There's a handful of guys in the NBA that have become the focal point of where your eyes go and he's one of them for me."

Witten: We have similar work ethics

Nowitzki was 20 when the Mavericks traded with the Milwaukee Bucks for the No. 9 overall pick in the 1998 NBA draft. Tight end Jason Witten was 20 when the Cowboys drafted him in the third round of the 2003 NFL draft.

In 15 years, Witten became the Cowboys' all-time leader in games played, games started, receptions and receiving yards. He played in 11 Pro Bowls in his first 15 seasons.

Folks marveled at his longevity, just as they marvel at Nowitzki's.

"That doesn't happen by accident," Witten said. "He embraced new teammates. He embraced new systems. He's done it all while still playing at this extremely high level, from early on in his career with Don [Nelson], then with Avery [Johnson]. He's just seen so many different things. The thing I respect most about him is you hear guys like Nash talk about how smart he is, Jason Kidd how smart he is. His basketball IQ was just off the charts. He's so much more than a 7-footer that could shoot. He never got bored with improving, never got bored with anything, and for any athlete, that's the blueprint. That's how you go have success."

When Witten held a retirement party last summer, Nowitzki attended. Over the years, they became friends, relaying their "secrets in the dirt," but also their philanthropic work that both do in and around Dallas.

"He just loves the work to get ready to play," Witten said. "Even to this day I think he still enjoys all the intricacies that go into him being successful. It's kind of similar, to me, with route running. There's an art to all of that. When you hear guys like Rick Carlisle talk about how diligent he was in that approach and in shooting mechanics, that's the secret."

Ellis: Dirk lasted longer than I did

Nowitzki's perspective on the Cowboys is interesting. He started playing for the Mavericks when the Triplets (Michael Irvin, Troy Aikman and Emmitt Smith) were trying to recapture their Super Bowl magic with the Cowboys and is likely ending it as a new trio (Dak Prescott, Ezekiel Elliott and Amari Cooper) try to bring the franchise back to Super Bowl relevancy.

The Cowboys' perspective on the sixth-leading scorer in NBA history is as interesting. Two months before the Mavericks traded for Nowitzki in 1998, the Cowboys selected defensive end Greg Ellis with the No. 8 overall pick of the NFL draft, famously passing on receiver Randy Moss.

In 11 seasons with the Cowboys, Ellis had 77 sacks. He led the team in sacks six times and was named to the Pro Bowl once.

"Well, he [Nowitzki] lasted a lot longer than I did," Ellis joked.

Ellis retired after the 2009 season with the Oakland Raiders. He's now 43 and producing movies and stage presentations. He played junior varsity basketball at North Carolina for Dean Smith and would practice against Vince Carter and Antawn Jamison, so he knows his basketball.

"I was 34 when I retired," Ellis said. "The reality of life in football especially is, 'OK, you're 34? Time to put you in a wheelchair.' But in the regular world, 'You're only 34?' It's like, wow. People way older than you look at you like you're a teenager."

A knee injury ended Ellis' career a year or so earlier than he expected. After 11 years, he reached all of his individual goals but admitted there were times he wanted to play again.

And now?

"I would rather take a chance playing a play on a basketball court then on a football field," Ellis said. "Maybe we can pre-arrange that they're going to run the ball to the other side where I can pursue at a nice steady pace."

Dallas has always been a football town with some of the most historical figures of the sport calling it home over the years, but Nowitzki has found himself alongside those greats in his 21 years with the Mavericks.

"Dirk Nowitzki is and will always be the Dallas Mavericks, the way we talk about the Roger Staubachs, Troy Aikmans, Michael Irvins, Emmitt Smiths and Bob Lillys," Romo said. "You just don't find in life somebody that you would argue is a top-10 player in the history of their sport -- and I can argue after getting to know him and his wife, Jessica, through the years -- that [he] might be better off the court. He's exemplified everything that Dallas and this community is about. He is genuine. He is real. He is caring.

"And he's 7-feet tall. Good luck finding that again."