The 2025 Boston Celtics Summer League campaign offered fans, analysts, and front office personnel a unique window into the franchise’s short-term and long-term future. While Summer League results never tell the full story, and stats often have to be taken with a grain of salt, there are always a few key takeaways that help shape what to expect going into the NBA regular season. Whether it was breakout performances, flashes of defensive prowess, or a clearer vision of roster roles, the Celtics’ Summer League team in Las Vegas left behind a trail of valuable lessons. For a team fresh off a championship season and trying to maintain its elite status while developing young talent, these lessons carry significant weight.
The first thing we learned from the Celtics’ Summer League run is that JD Davison may be ready for more consistent NBA minutes. Now entering his third year, Davison has long been a raw but electric talent, someone who’s shown sparks of brilliance but lacked the polish to crack the regular rotation of a title-contending squad. That seems to be changing. Over the course of Summer League play, Davison demonstrated a mature control over the game. His decision-making, previously seen as a weakness, has dramatically improved. He ran the offense with purpose, kept turnovers low, and was aggressive without being reckless. His playmaking instincts were on full display, threading passes through tight windows and keeping teammates involved. More importantly, his perimeter shooting looks more stable, with a higher release and better balance. With the Celtics possibly thinning out their backcourt depth depending on offseason moves, Davison has made a strong case to earn a role as a rotational guard — or at least as an emergency plug-in who won’t hurt the team when called upon.
Another major observation centered around Jordan Walsh, the high-upside wing Boston drafted in 2023 who spent much of his rookie year toggling between the G League and bench minutes. Summer League gave Walsh a bigger stage to showcase what he’s been working on, and he responded with a much more well-rounded offensive arsenal. Defensively, he continues to be a pest — long arms, sharp anticipation, quick feet — but offensively, his ball-handling and pull-up game showed significant strides. What once was a “just defense and energy” player is now looking like someone who could be a legitimate two-way contributor. Walsh attacked closeouts, navigated in pick-and-rolls, and even hit some difficult mid-range shots — all indicators of a player who’s evolving past the “project” label. He still has room to grow, especially with consistency from three-point range, but his growth trajectory suggests the Celtics have a valuable wing developing under the radar. With veterans like Jayson Tatum and Jaylen Brown unlikely to log heavy preseason or early season minutes, Walsh may find opportunities to further stake his claim to a backup wing role.
The third key takeaway involves rookie sharpshooter Baylor Scheierman, whom the Celtics drafted in the second round of the 2025 NBA Draft. Known primarily for his shooting at Creighton, Scheierman arrived in Las Vegas with the reputation of a catch-and-shoot sniper. He lived up to that billing — and then some. What surprised many was his versatility as a shooter. He wasn’t just spotting up in the corners or wing; he was relocating off screens, pulling up off the dribble, and even coming off pin-downs in motion. That kind of shooting gravity is rare in young players, and it’s something Boston’s bench units could sorely use in spurts. Furthermore, Scheierman displayed underrated court vision and defensive awareness. He made smart, quick passes out of traps and rotated well on defense, never looking overwhelmed by the pace of the game. His ceiling may not scream “future All-Star,” but his floor seems to be rising rapidly as a dependable role player who fits the Celtics’ system. Don’t be surprised if he earns a two-way contract or even a full roster spot by training camp if the roster math allows it.
In a more tactical observation, the fourth thing we learned was that the Celtics’ Summer League coaching staff emphasized a style of play consistent with the big club’s identity. That continuity is crucial for player development. The offense featured five-out spacing, ball movement, and strong side-to-weak side actions reminiscent of Joe Mazzulla’s system. Defensively, they switched often and applied pressure on the perimeter, betting on team speed and length. It’s not just about evaluating talent — it’s about preparing that talent to seamlessly fit into the larger system when called upon. Players like Neemias Queta and Drew Peterson, who’ve already been around the Celtics’ G League environment, seemed more comfortable executing these principles. That speaks volumes about how the organization has built a developmental pipeline that isn’t disjointed but directly feeds into the NBA team’s schemes. Whether or not many of these Summer League players ever become rotation guys, the Celtics are instilling a professional, system-first identity early in their careers, and that bodes well for future plug-and-play situations.
A fifth insight revolves around the front office’s commitment to internal development over headline-grabbing acquisitions. The Celtics are fresh off a championship, and it would be easy for Brad Stevens and the front office to go all-in on veterans, ignoring the pipeline. But this Summer League suggests that the organization values grooming young talent and maintaining cost-effective contributors. The steady performance of players like Davison and Walsh, combined with intriguing flashes from rookies like Scheierman and even fringe names like Reggie Perry and Anton Watson, highlights a long-term vision. These aren’t just bodies to fill a Summer League roster; they’re being groomed with real purpose. Even if only one or two pan out, that can mean millions saved in the salary cap era — and, more importantly, depth in a long playoff run. While teams like the Suns and Clippers shuffle through aging stars, the Celtics appear content building a supporting cast organically, blending youth and experience.
Lastly, perhaps the most understated yet crucial thing we learned from the Celtics’ Summer League is that the franchise’s culture remains intact and infectious. Players were engaged from the bench, celebrating stops and baskets like playoff wins. Coaches were hands-on, holding players accountable while offering encouragement. Executives, including Brad Stevens, were visibly present and observant, reinforcing that every detail matters. That kind of engagement trickles down from the top and fosters accountability among players. Even in games that didn’t go their way, the Celtics’ Summer League squad fought hard, played smart, and competed with purpose. It wasn’t just about highlights or numbers — it was about building habits. For a championship team looking to remain dominant in the post-title era, culture becomes the most important asset. And from the looks of it, Boston’s culture is as strong as ever, anchored by principles of effort, execution, and unity.
The Celtics’ 2025 Summer League performance may not change the national narrative or dominate headlines, but it provided the kind of internal validation championship teams rely on to stay elite. From emerging contributors like JD Davison and Jordan Walsh to rookie revelations like Baylor Scheierman, Boston has reason to be optimistic about its developmental core. The commitment to continuity in coaching philosophy, the strategic investment in young talent, and the preservation of a winning culture all point toward a franchise that isn’t resting on its laurels. Instead, the Celtics appear more committed than ever to maintaining their edge, not just through stars and trades, but through careful, deliberate development. That’s what makes a team sustainable, and the 2025 Summer League served as a reminder that Boston’s foundation is not only solid but evolving in all the right ways.
