Tarik Black made his way to the Toyota Center court for the opening of Rockets training camp when he noticed how much things had changed since he last made that walk.

He was not looking at his group of teammates, with just three - James Harden, Trevor Ariza and Clint Capela - still around from his rookie season. He was not considering the remade coaching staff or even the (slightly) revised uniforms.

As Black took the floor, it hit him how greatly he had changed since 2014 when he was hoping to beat the odds to earn a place on a roster.

"I just thought about my rookie year, when I was in the locker room before we walked out, how nervous and anxious I was before we came out," Black said. "I was the first one on the floor. My hands, my body were all stiff.

"Walking out in this arena, the circumstances, the situation, just how much different. It shows me how far I've come in my career."

The Rockets signed Black to a one year, $3.29 million contact in July to fill the third center position manned last season by Montrezl Harrell. The Rockets do not view the role as insignificant. Harrell played in 58 games last season, filling in when Nene was given games off as the 15-year NBA veteran likely will be again this season, or when Capela was hurt.

"He is a third center, but … Nene is kind of in a special category," Rockets coach Mike D'Antoni said. "We need to rest him some. He needs to have limited minutes so we can get him all the way through the year and the next three or four years.

"I think (Black) is perfect for that role. Tarik has one of the hardest roles on the team. Some nights he might get very little minutes or no minutes and then respond. Like Montrezl last year, Montrezl might play great for a stretch, but then not play for a couple games. It's not easy. But Tarik understands and whenever we call on him, I think he'll respond with a lot of energy."

When weighing options to fill that role, the Rockets had to consider Black's willingness to accept that role as much as his skills. D'Antoni called that a "pretty easy call." But Black also had to have improved since he surprisingly edged veteran Jeff Adrien for a roster spot in 2014.

"For one, first and foremost. I solidified. I'm an NBA player," said Black, who was waived Dec. 26 that year to open a roster spot for Josh Smith. "Coming in training camp at that time, I was undrafted, non-guaranteed contract. The situation was very sticky for me. In this situation, I think there's no question I'm an NBA player. That brings much more confidence on the floor.

"Now, I get on the floor, with this amazing team, it's just a totally different situation because now, I'm a part of it. I'm a part of why we're going to be a great team."

The Rockets have seen the difference. Black played a limited role with the Lakers, averaging 5.7 points and 5.1 rebounds in 16.3 minutes per game. The Rockets have noted, however, that he defends like the veteran he has become.

"I think he slowed down a little bit," Ariza said. "I think he understands the game more. When you're a rookie, everything is moving really fast and it takes a while to adjust to that. His knowledge of the game has grown. He plays with a lot of energy still."

Black described his job with an understanding that there will be games in which he does not leave the bench. At 6-9, 250, he is bigger than Harrell and considered a stronger defender and defensive rebounder, if not as effective as a finisher (though a 54.2 percent shooter in his first three seasons.)

"Above all things, for anybody, it's to be a great teammate, to uplift everybody around us," Black said. "Everybody is wearing this name (Houston) right here. That's what it's really about. After that, it's just to grow for me. I'm only 25. It's my fourth year. Just grow, talk to the coaches, see how I can become a better player and fit this role that I have here better.

"I've proven that I'm a defensive presence in this league. You know when I get on the floor how I'm going to perform. You can switch certain things. How I get steals. How I protect rim. I'll move my feet whether you want to switch with me or not. You know those things and I know those things before I walk in the gym."

The Rockets did not know any of that three years ago. Even Black could only guess. He was overlooked with a first name often mispronounced 'Tareek' instead of 'Tah-rick." When he returned, he could take a moment to enjoy how far he had come.

"It feels great," Black said. "The first time, I was undrafted, a fully-guaranteed roster. Just walking in this gym the first time was a fight. It worked out great, tremendous."

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