When a veteran on the Nets asks Day’Ron Sharpe to do something, most of the time he has to say yes. That might mean making a plate of food for James Harden after a game or getting doughnuts beforehand. Other times, he has to turn the showers on in the locker room or carry the veterans’ bags.

“The rookie dudes, we’re getting nothing compared to what they had to do,” Sharpe, 20, said.

He added, “Just because you’re starting doesn’t mean they stop.”

When Sharpe came to training camp, he expected to sit on the sidelines for much of the season. He was a late first-round pick coming to a team that was, at least on paper, one of the best in N.B.A. history. It was filled with veterans and top stars and favored to win the championship. Instead, Sharpe, a bulky center most comfortable absorbing hits in the paint, is a crucial player for the Nets more than halfway through the season. He was moved into the starting lineup a few weeks ago and is averaging 9.3 points and 6.8 rebounds on 58.8 percent shooting in January.

“It’s crazy for me to be able to contribute,” Sharpe said.

It’s not just Sharpe. Cam Thomas (another late first-round draft pick), Kessler Edwards (second-rounder) and David Duke Jr. (undrafted) have also received significant playing time. All four have spent part of the year with the Nets’ G League affiliate, the Long Island Nets. It is unusual for a championship contender to give such prominent roles in the rotation to this many first-year players, especially ones who weren’t highly touted. The Nets are one of two teams to have four rookies who average at least 10 minutes per game and have appeared in more than 10 games. The other is the Oklahoma City Thunder — a rebuilding franchise ranked near the bottom of the league.

Rookies have performed remarkably en route to a championship, such as Magic Johnson, who led the Los Angeles Lakers to a title in 1980, and Bill Russell, who did the same for the Boston Celtics in 1957. But Johnson, who was drafted first overall, and Russell (No. 2) were top-tier draft picks who immediately became the faces of their teams.

The Nets have successfully relied on rookies before. During the 2001-2 season, they leaned on four: Richard Jefferson, Jason Collins, Brandon Armstrong and Brian Scalabrine. Jefferson and Collins each started nine times and took the floor almost every game, while Armstrong (35 games) and Scalabrine (28) were important contributors as well. The team made the finals.

This year’s Nets are hoping to repeat, and surpass, that success using players who typically would be called upon this much only in a “break glass in case of emergency” situation.

The glass broke. Between Covid-related absences, including Kyrie Irving’s, and injuries to key players like Kevin Durant, the Nets have needed bodies — at times, almost anybody — to take the floor. Irving has not been eligible to play in home games because he refuses to get vaccinated against the coronavirus, and for much of the season the team barred him from road games as well.

But Coach Steve Nash has turned to the rookies even when it wasn’t an emergency. He has experimented with lineups at close to full strength. Duke, 22, has started seven games, some of them alongside Harden and Durant. On Jan. 12 against the Chicago Bulls, the Nets started Edwards, Sharpe, Harden, Durant and Irving.

Before a recent road game against the Washington Wizards, Nash said that the lineup tinkering was a result of wanting to “look at all the new guys.” The Nets rarely practice, which is common for veteran teams. As of Thursday, the Nets had used 24 starting lineups, tied with the Philadelphia 76ers for most in the N.B.A. But Nash also said that the shuffling had been a matter of “necessity.”

“How many guys are available? When we land on a stretch where there are many guys available, what stretch did we just come out of?” Nash said. “Who is playing well? Who fits? So a lot of it is to try and make common sense. And if it doesn’t seem like there’s common sense from the outside, there’s probably something from the inside that leads us to make these decisions that is a private matter.”

The Nets rookies have received playing time at the expense of veterans. Blake Griffin, a six-time All-Star who seemed to be slated for a core rotation spot, was removed from the lineup early on, resurfacing there only when the Nets were otherwise depleted. He’s playing a career-low 18.1 minutes a game and has performed poorly overall, shooting only 38 percent from the field. Paul Millsap, a four-time All-Star, was signed in free agency to be a backup, an addition thought to be a coup at the time. But the 36-year-old couldn’t find his footing, and Nash told reporters this month that the team was looking to find a new home for him.

“You add it all up, and there’s just not enough space for everybody,” Nash said.

Thomas, a 20-year-old who spent one year at Louisiana State University, has been the most impactful rookie of the four, receiving consistent minutes off the bench as a skilled scorer. He hit a game-winning floater against the San Antonio Spurs earlier this month. Thomas said in an interview that the best advice he’d received had come from Rajon Rondo, the Cleveland Cavaliers point guard who won a championship as a starter for the Celtics in only his second year.

“He said, ‘However you came up, through high school, college and all that, keep doing that, because that’s how you got here,’” Thomas said.

For a team like the Nets, finding steals at the end of drafts (or in the case of Duke, past the draft) is a must, said General Manager Sean Marks. The Nets have minimal cap space, since much of it is tied up in Harden, Irving and Durant. Getting free agents to take pay cuts and finding overlooked talents result in less expensive contracts. And there’s an added benefit to feeding rookies playing time: Showcasing them can increase their trade value and give the Nets another route to add better players.

“We’ve had to adjust how we build a team starting six years ago from now, right?” Marks said, adding, “It’s fun when you’re in a war room, when you’re on a draft day and the room erupts because of who you drafted in the 30s and 40s and 50s

But there are drawbacks, too, when you have constantly shifting lineups.

“It does make it a little bit more challenging, I think, but that’s the way that it’s been with everything that we’ve been through,” Patty Mills, a 33-year-old guard for the Nets, told reporters. “But to be a professional, especially in this league, you need to learn how to adjust on the fly.”

And as might be typical for young players thrust into unexpected roles, the four rookies have been inconsistent. Duke is back out of the rotation. The Nets are 6-9 in January and just the fourth seed of the Eastern Conference, well below preseason expectations. Much of the offensive load has fallen on Harden, given a knee injury to Durant that will keep him out for several weeks and Irving’s scattered unavailability. Sharpe and Edwards, now starting, aren’t playmakers — although Edwards is a reliable shooter (39 percent from 3). This puts more of an onus on Harden to do more to keep the Nets afloat.

That’s likely unsustainable. Nash will probably have to keep changing rotations, giving larger roles to Mills, Griffin and the veteran center LaMarcus Aldridge as the playoffs approach. But with Nash’s Nets, nothing ever goes according to plan, and these rookies have shown that they’re not simply understudies on a Broadway production.

Asked what he would have said in the fall if he were told he’d be starting at midseason, Sharpe said: “Man, I don’t even know. Because at training camp, that was my first time being with the guys and all that. I’m seeing how they’re hooping and stuff, thinking ‘I’m probably not even touching the court this year.’”