It was going to be the shining moment in Carmelo Anthony's return to the NBA. Just 15 minutes into his debut with the Portland Trail Blazers, the 10-time All-Star rose up for an epic posterizing slam. There was just one problem, and his name was Jaxson Hayes.

"I thought he was going to try and lay it up," Hayes said after the game.

The No. 8 overall pick, himself making just the second start of his career, denied Anthony's dunk attempt, one of three blocks he had in what turned into a 115-104 win for the New Orleans Pelicans.

A month earlier, when the season began, Hayes found himself in a far different position: glued to the bench. But injuries have forced Hayes and fellow first-round pick Nickeil Alexander-Walker into much bigger roles far earlier than expected.

With No. 1 overall pick Zion Williamson shut down after just nine minutes of summer league action in Las Vegas, it was New Orleans' other two first-round picks who shined in the Las Vegas spotlight.

Alexander-Walker, the No. 17 overall pick out of Virginia Tech, was a first-team All-Summer League selection, after averaging 24.3 points, 6.0 assists and 4.3 rebounds per game. Hayes, meanwhile, provided Zion-like highlight dunks and posted averages of 16.3 points and 7.3 rebounds. Still, when the regular season arrived, both were out of the rotation.

Alexander-Walker averaged just 13 minutes per night in the first three games of the season, all while shooting a dismal 17% from the field. Hayes didn't play at all in those games and looked like he was going to spend the 2019-20 season sitting and watching. Pelicans executive vice president of basketball operations David Griffin went on record during the summer saying the team initially thought of this season as more of a "redshirt" year for the No. 8 overall pick from Texas.

But on Oct. 28 against the Golden State Warriors, thanks to a combination of injuries and a score that got out of hand in favor of the new tenants in San Francisco, Hayes and Alexander-Walker each had their chance to shine.

That night, the Pelicans fell behind by 17 points at halftime and were down 24 entering the fourth quarter. With the game out of hand, head coach Alvin Gentry gave his rookies extended run.

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"I don't think anything can [top] the experience of being in the game," Gentry said last week. "Learning from your mistakes or just figuring out what you can do to help the team in a positive standpoint. Hopefully this is something that can help us down the road."

In his first regular-season game, Hayes had 19 points on 9-of-11 shooting -- and one of those misses was a desperation three-pointer from the other side of the court. He also recorded his first blocked shot against two-time MVP Stephen Curry. Meanwhile, Alexander-Walker seemed to have a breakthrough with 15 points and nine assists on 6-of-11 shooting.

"Garbage time is another man's opportunity to find his rhythm and confidence," said Antonio Daniels, who serves as the New Orleans Pelicans' television color commentator. "Coaches used to tell us, if you're in the end of the game like that, you can find your stroke."

Since that night, with the Pelicans' injuries piling up and the team lacking healthy bodies, the rookies' roles have continued to expand.

When the Pelicans were down to eight healthy players against the Heat on Nov. 16 and nine players against the Warriors the following night, Alexander-Walker averaged 23.0 points, 4.5 rebounds and 3.5 assists while hitting 11-of-22 from 3-point range. He's played at least 20 minutes four times this season. In those four games, he's averaging 16.0 PPG while shooting 45.8% from long distance.

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He insists he's taking the same shots he took early in the season -- they're just falling more now, like they did in the preseason, when he went 14-of-30 from beyond the arc. Still, his unflappable approach to the game has earned him the respect of his teammates.

"He might be my favorite player on the team," All-Star point guard Jrue Holiday said earlier this season. "Kiel, the way he's coming in, being fearless. It's pretty cool."

Meanwhile, Hayes was thrust into the starting lineup due to injuries to centers Derrick Favors and Jahlil Okafor. Favors left the Miami game with back spasms. After replacing him in the starting five, Hayes averaged 2.3 blocks per game over his first four starts.

Gentry said the 6-foot-11, 220-pound Hayes still has a ways to go on defense, but part of that will come as his body continues to fill in.

"I think he understands that. Part of that is having the strength to hold your position and the core to hold your position," Gentry said. "At 19, his body is still developing. The more he's out there, the more I think it will help."

Hayes said he doesn't feel like a deer in the headlights on defense anymore, and he credits the early playing time in low-pressure situations with helping him get adjusted so quickly.

"Just getting that rhythm and getting used to play a lot more definitely helps," he said. "Whenever somebody can get a rhythm going, it can definitely help."

Both players figure to see their playing time cut when the Pelicans are at full strength, although Hayes could steal away some of Jahlil Okafor's minutes. But they all know their number could get called at any moment.

"Being a rookie, I just learned that being a professional means being ready at all times," Alexander-Walker said. "Guys can go out any minute. I might hear my name get called and be able to be perform."