HOUSTON -- The raw kid from Switzerland, the center with soft hands, springy legs and open ears, offered James Harden reason for optimism during the roughest year of the Houston Rockets superstar's career.

It was 2015-16, the final season of Harden's failed marriage with former All-Star center Dwight Howard. As their relationship fizzled due to differences in basketball philosophy, a major factor in a catastrophe of a 41-41 season, Harden saw potential in 21-year-old Clint Capela.

Capela's physical tools caught Harden's eye. His work ethic earned Harden's respect. His willingness to listen -- the word Harden uses most often when discussing Capela's development -- planted seeds of trust, allowing the bearded face of the franchise to believe he could help groom the project big man into an impact player who would perfectly complement his MVP-level game.

"I knew it wasn't going to happen right away," Harden recently told ESPN, "but I continued to work with him, and now look where he is."

Now, the 23-year-old Capela stands right in the middle of the Rockets' success, a blossoming star for a team that had the NBA's best record in the regular season and has won five of its first six playoff games. He embraces his role alongside Harden and appreciates the perennial All-NBA guard's guidance.

Capela has come a long way in a few short years since he was a wide-eyed rookie who missed the first 11 field goal attempts of his NBA career, a streak of futility that fittingly ended when he finished an alley-oop from Harden.

Capela has made dramatic improvement each season and is playing the best basketball of his life during this postseason, averaging 15.8 points, 13.8 rebounds and 1.8 blocks while matched up against established elite centers Karl-Anthony Towns and Rudy Gobert.

Count Harden as one of the first to see this coming from Capela, the 25th pick in the 2014 draft, who spent most of his rookie year with the G League's Rio Grande Valley Vipers.

"James is very smart," said Rockets general manager Daryl Morey, who has turned over the entire roster with the exception of Harden, Capela and glue guy Trevor Ariza in the past two years.

"[Harden] saw the potential -- [Capela's] ability to get off the ground quick, his ability to apply what he learned quick, his ability to finish around the rim, all that. I think James saw that early and really helped develop that."

Harden privately lobbied for Capela to get more playing time in 2015-16. While that was evidence of Harden's frustration with Howard, whose insistence on post touches bogged down the Rockets' offense, it was also a strong vote of confidence in Capela.

"He was sitting at the kids' table at the wedding for a long time. Now he's up giving toasts."

That confidence was also consistently expressed directly to Capela. Harden frequently gave Capela positive feedback and took time to teach the big man intricacies of the game, such as how to position himself to receive passes around the basket, molding Capela to become the pick-and-roll partner Howard balked at being.

"He was telling me that he liked to play with me," Capela told ESPN. "He liked that I was always putting in energy. We were struggling that season, but I was always doing the good stuff. It makes me feel good that a player like him believed in me at first. I was a young player surrounded by veterans. It made me feel good that the main guy believed in me."

Harden's hand in Capela's rapid growth offers a strong counterargument to former Rockets coach Kevin McHale's harsh take this fall on The Beard's leadership skills, or lack thereof. That criticism stung Harden, who responded by calling McHale "a clown."

But the development of Harden and Capela into arguably the league's most lethal guard/center duo is no laughing matter.

Best Assists-To-Scorer combos in the NBA (2017-18 Reg. Season) SCORER ASSIST TEAM AST Steven Adams Russell Westbrook OKC 229 Clint Capela James Harden HOU 198 Jusuf Nurkic Damian Lillard POR 190 Paul George Russell Westbrook OKC 181 Anthony Davis Rajon Rondo NO 164

According to NBA.com statistics, Capela scored on assists from Harden 198 times this season, which is more than twice as many times as Howard finished on feeds from Harden during their final season together. That ranked second in the league this season behind Oklahoma City's Russell Westbrook feeding Steven Adams among assists from one teammate to another.

Harden-to-Capela has been even more prolific during the postseason, with the probable MVP assisting on half of the big man's 42 buckets through six playoff games, including five feeds for dunks or layups during Capela's 16-point, 12-rebound performance in Sunday's Game 1 victory over the Utah Jazz.

On one play in the second quarter, Capela had his hands on his knees with a foot out of bounds on the baseline, a couple of steps out of the paint, as Harden danced with the ball at the top of the arc. Harden blew by Royce O'Neale, driving down the left side of the lane and drawing Gobert to the front of the restricted area.

As soon as Gobert stepped toward Harden, Capela sliced down the baseline, presenting himself as a target to Harden, who floated a lefty lob to the big man for the easy layup as the probable Defensive Player of the Year was caught helplessly flat-footed. It's one of the simplest, most unstoppable plays in the NBA.

How can one defender take away Harden's layup and the lob to Capela? It's especially difficult, given Harden's innate ability to wait until the defender commits to make a decision, and the perfect rhythm the Rockets' duo has established, whether it comes from a Harden iso or a pick-and-roll.

"It's really more about the feel of the game," Capela said, who has finished 129 alley-oops this season, according to NBA.com tracking -- 112 coming on feeds from Harden. That includes all 14 of Capela's alley-oop finishes during the playoffs.

They've reached a point where Harden rarely pulls Capela aside to discuss offensive details. They click off of feel now.

Capela knows exactly how Harden wants his screens set and when to anticipate a fastball bounce pass -- one few big men in the league can handle as smoothly as Capela, who possesses a rare ability to pluck a low pass and explode to the rim in one motion -- or a lob. Capela understands the rhythm of when to dart to the rim late when Harden attacks the basket on an iso. He can read Harden's eyes and know he's looking to throw an alley-oop from half court.

James Harden always seems to know the right time to make a pass to teammate Clint Capela. Troy Taormina-USA TODAY Sports

Those are all lessons that Capela has learned well, soaking in the wisdom Harden offered.

"That's everything," Harden said. "A lot of young guys don't listen. They know everything. They want to go out there and just run. Obviously, myself and now Chris [Paul] coming in, communicating and talking to him, a guy that listens and works his butt off, he's going to be successful.

"A guy that doesn't [listen] and thinks he knows everything, you know where those guys end up."

Harden's preference for playing with Capela over Howard could have been fodder for controversy at the time, but it was supported by analytics. The Rockets had a net rating of plus-3.7 points per 100 possessions when Harden and Capela were on the court together in the 2015-16 season, compared to plus-2.3 when Harden was paired with Howard.

"I was in that same situation -- playing behind somebody when I first got into the league and then finally getting my opportunity and then taking advantage of it," said Harden, a sixth man for the Thunder behind Kevin Durant and Westbrook before being traded to the Rockets. "That's what it's about. So I can relate to what he's come from. He works his butt off every single day. That's the reason that he's so successful."

The Harden-Capela combination really took off after the hiring of offensive guru Mike D'Antoni as coach. The duo's net rating shot up to plus-9.2 last season, Capela's first year as a full-time starter. Their net rating bumped up to plus-10.5 this season, and it has taken another leap to plus-13.8 during the playoffs.

All the while, Capela is becoming a more and more critical part of the Rockets' machine. He provides the vertical spacing on his offense that helps create open perimeter looks for a Houston team that broke the NBA's record for 3-pointers made in two straight seasons. His rim protection anchors a drastically improved Rockets defense, and his quick feet enable Houston to employ the switch-everything scheme that has been a big part of their success on that end of the floor.

"He was sitting at the kids' table at the wedding for a long time," said D'Antoni, who refers to Capela as the best player at his role in the NBA. "Now he's up giving toasts."

Harden will happily raise his glass to that.