The WNBA playoffs begin on Sunday without three of the league’s most electrifying young stars: Caitlin Clark, Angel Reese, and Paige Bueckers. Their absence isn’t just a missed opportunity for fans; it could have an adverse impact for the players’ union during its negotiations with the league on a new collective bargaining agreement.

The three players are at the heart of the WNBA’s surge in popularity, driving record attendance, viewership, and social media buzz. Ms. Clark, the first overall draft pick in 2024, was the Rookie of the Year last season, and Ms. Bueckers, the top choice in 2025, is expected to earn the same honor this year. Meanwhile, Ms. Reese has led the league in rebounding for two consecutive seasons and remains a strong voice in league matters. Any conversation about the future value of the league starts with them.

Yet, none of them will be able to showcase their skills during the post-season when the spotlight is the brightest. Although the Indiana Fever made the playoffs for the second consecutive season, Ms. Clark is out for the remainder of the year with a groin injury that has kept her sidelined since July. Ms. Bueckers, meanwhile, set the rookie scoring record for the Dallas Wings, but her team’s dismal year kept them out of the playoffs.

The Chicago Sky also failed to make the playoffs, leaving Ms. Reese out of the post-season for the second straight year, something she wasn’t very happy about. “I’m not settling for the same [thing] we did this year,” Ms. Reese said recently. “We have to get good players. We have to get great players. That’s non-negotiable for me.”

The Sky suspended her for the first half of its game with the Las Vegas Aces on Sunday for those comments, an action that isn’t going to endear her to the team once her contract expires next season.

The league has benefited enormously from the popularity and visibility the young stars generate. The WNBA signed a record $2 billion television rights deal last year, nearly doubled its expansion fees, and enjoyed record attendance throughout the league. The players, wanting a larger piece of the revenue, opted out of the current CBA, which expires next month. Negotiations on a new deal haven’t produced much progress, leaving some players frustrated.

“I think there’s a lot more we want as players and that we’re going to try to demand,” Ms. Bueckers said earlier this season. “We don’t want to sound ungrateful for all the stuff that the WNBA provides, but we think as much as we sacrifice our bodies, our minds, our time, our effort, we just feel like we play a huge part in this as well. And we feel like we should be rewarded for that.”

Without its three young stars, the WNBA must shift the narrative to its established legends, who must carry the weight of the postseason. A’ja Wilson of the Las Vegas Aces and Napheesa Collier of the Minnesota Lynx are locked in a close battle for the 2025 WNBA MVP award.

The Lynx have clinched the no. 1 seed and home-court advantage throughout the playoffs, but the Aces carried a 15-game winning streak with two games remaining in their regular season. Ms. Wilson, a three-time league MVP, set a WNBA singles season record for most 30-point games with 13 after Sunday’s game.

Offering added drama are the reigning champion New York Liberty. Despite a season plagued by injuries to key players like Jonquel Jones, Breanna Stewart, and Sabrina Ionescu, the Liberty enter the playoffs healthy and optimistic. As the no. 5, they’ll have to make history to successfully defend their title. No team has ever won the championship as a fifth seed.

“We kind of get a fresh start in the playoffs,” Ms. Ionescu said. “Everyone is 0-0. What you did in the regular season, the adversity that you faced can only make you stronger.”

Despite Ms. Clark playing in just 13 games, the WNBA viewership has remained strong. Through 56 nationally televised games, the league averaged 794,000 viewers, a 21 percent increase from last year’s full season average, according to Nielsen data. Fever games averaged 1.26 million. Interestingly, non-Fever games are up 37 percent from last year, averaging 549,000.