When the Boston Celtics (43-21) last faced the San Antonio Spurs (47-17), the night served as a reminder of how thin the margin can be between control and collapse.

For three quarters at TD Garden, Boston largely dictated the terms.

The Celtics defended with discipline, forced San Antonio into uncomfortable perimeter looks, and leaned on strong performances from Jaylen Brown and Derrick White to maintain a narrow advantage.

But when the fourth quarter tightened - when execution and secondary scoring became critical - Boston ran out of answers.

San Antonio closed stronger behind Victor Wembanyama, whose late shot-making helped push the Spurs to a 100-95 victory. The loss didn’t feel like a collapse so much as a lesson: even when the Celtics control large stretches of a game, the margin for error against elite size and star power can disappear quickly.

Now the two teams meet again under very different circumstances.

Boston enters the matchup riding renewed momentum following the return of Jayson Tatum, whose long-awaited comeback from an Achilles injury has immediately shifted the tone of the Celtics’ season.

After missing the opening months of the year, Tatum has already begun reasserting himself as the centerpiece of Boston’s offense while still working within a managed minutes load.

In his first two games back, the Celtics have looked noticeably steadier offensively, with Tatum’s presence creating easier looks for Brown and the rest of the rotation.

That ripple effect has been especially noticeable for Boston’s supporting cast. Payton Pritchard has continued to thrive in a playmaking role off the bench, while players such as Sam Hauser and Baylor Scheierman have benefited from the additional spacing created when defenses must account for Tatum.

The Spurs, meanwhile, remain one of the Western Conference’s most intriguing teams thanks largely to the continued growth of Wembanyama. Even on nights when his stat line appears modest, the 7-foot-4 phenom has a way of shaping games with his size, rim protection, and late scoring bursts - as Boston learned firsthand in their previous meeting.

That earlier matchup offered a clear blueprint for both teams.

For the Celtics, the challenge will be closing stronger than they did in January.

For the Spurs, the formula remains simple: keep the game within reach long enough for Wembanyama to tilt it late.

If the first meeting was any indication, tonight’s rematch should once again be decided in the margins.

Boston Celtics at San Antonio Spurs Information

Game Date: March 10, 2026
Game Time: 8:00 PM ET
TV Channel: NBC (National), NBC Sports Boston (Boston) & FanDuel Sports Network Southwest (San Antonio)
Radio: 105.7 WROR (Boston) & 1200 WOAI (San Antonio)
Location: Frost Bank Center
Live Stream: Peacock, Fubo & NBA League Pass

Missed any of Sunday afternoon’s win over Cleveland? Here’s everything you need to know:

Even on a minutes restriction, Tatum wasted little time asserting himself.

The Celtics star logged 28 minutes and came out aggressively, scoring 12 points in the first quarter alone while attacking Cleveland’s defense in a variety of ways.

Tatum mixed pull-up jumpers with strong drives to the rim, including several finishes through contact against Evan Mobley.

The three-point shot wasn’t falling - Tatum struggled to find rhythm from beyond the arc and missed several perimeter looks after his strong opening quarter.

Still, his overall impact remained clear as he finished with 20 points and helped keep Boston’s offense organized.

Most importantly, he looked physically comfortable.

For a player returning from a lengthy injury absence, that’s the biggest takeaway of all.

The Cavaliers simply could not buy a basket in the second quarter.

Cleveland managed just 10 points in the entire frame and scored only two points over the first 7:21 of the period.

The Cavaliers shot 4 of 25 from the field, and missed all 14 of their three-point attempts during the quarter.

Aside from Mobley and Mitchell, Cleveland’s roster combined to shoot 0 for 15 in the period.

That brutal stretch allowed Boston to completely flip the game.

What started as an early deficit quickly turned into a comfortable halftime lead that the Celtics never relinquished.

One of the biggest ripple effects of Tatum’s return is that several players are sliding back into smaller roles - and those players are thriving.

Boston’s bench outscored Cleveland’s reserves 19-2 in the first half and remained impactful throughout the afternoon.

Pritchard was especially important, finishing as a plus-18 in 32 minutes while orchestrating the offense for long stretches.

Baylor Scheierman also delivered one of his strongest performances of the season, recording a double-double and knocking down key shots as Boston built its lead.

During a crucial third-quarter stretch, Boston went on a 16-2 run with Tatum and Derrick White both on the bench - a testament to how deep and balanced the Celtics roster remains.

Many expected a lengthy adjustment period once Tatum returned from his injury.

So far, that hasn’t happened.

Boston has looked sharp in the early stages of Tatum’s return, with the star forward already playing close to 30 minutes and the team’s supporting cast continuing to excel in more natural roles.

Sunday’s game was also a useful measuring stick against a legitimate Eastern Conference contender.

The results were convincing.

Boston controlled the game defensively, dominated the bench battle, and ultimately showed a level of depth that few teams in the conference can match.

If Tatum continues to ramp up without setbacks, the Celtics’ margin for error in the East may become very small.

For the rest of the conference, that’s a troubling sign.

Remember to join our CELTICS on ROUNDTABLE community, which is FREE! You can post your own thoughts, in text or video form, and you can engage with our Roundtable staff, as well as other Celtics fans. If prompted to download the Roundtable APP, that's free too!

Tom Carroll is a contributor for Roundtable, with boots-on-the-ground coverage of all things Boston sports. He's a senior digital content producer for WEEI.com, and a native of Lincoln, RI.