For most of the 2020s, defense for the Boston Celtics has been a hallmark.

In the early part of the half-decade, it was Defensive Player of the Year Marcus Smart leading the charge, rim protectors Robert Williams and Al Horford, and an improving Jayson Tatum on the wing. Former head coach Ime Udoka instilled that hard-nosed mentality, and the team bought-in to the tune of an Eastern Conference title and a trip to the 2022 NBA Finals.

Fast forward to the 2023-24 season, and Boston was armed with a future Hall of Fame guard in Jrue Holiday and unicorn big man Kristaps Porzingis, two players who immediately make you better defensively the minute they hit the floor together. Add those stars to a mix with a fully-formed Tatum and still-high performing veteran in Horford, and you’re going to be among the best defensive teams in the league.

Icing on the cake was the growth of guard Derrick White, who had improved on both sides of the ball year-over-year since being traded to Boston from San Antonio in the middle of 2021-22 season. He had gone from a nice piece to a player that forced Boston to move on from Smart, giving White the runway to show the full breadth of his game both as a scorer and defender.

Fast forward to this year’s training camp, and things are looking a whole lot different for Boston on defense:

- Horford signed a multi-year deal with the Warriors

- Holiday was shipped off to Portland to help get the team under the second apron

- Porzingis was shipped off to Atlanta in a similar move with similar motivations

- Tatum is likely to miss the entire 2025-26 season as he continues to rehab his surgically repaired Achilles

All that remains from the key cogs in the Celtics defense is White.

Sure, Jaylen Brown flashes on defense at times, but anyone who has watched his career develop will tell you that he has regressed as a consistent perimeter scorer since entering the league. And there are no illusions to be had on Payton Pritchard’s ability as a defender - it’s the biggest weakness in his game.

So who does White expect to step up and be a leader with him on the defensive side of the ball?

In steps former Timberwolves forward Josh Minott, who Boston signed this summer during the free agency period to a two-year deal worth $5 million.

“He’s a pest,” said White during his media availability at day three of Celtics training camp on Friday. “He's got good size, arms are long, active hands, and so he can guard multiple positions. So it's been good to see him challenge himself, picking up. And he’s definitely - he’s gotten a lot of us.”

“What’s it like going up against him?” White was asked in a follow-up.

“Like I just said, he’s a pest,” White said with a smile.

At 6-foot-8, Minott has the versatility to do a lot of different things for Boston defensively. Throughout his first three seasons in the NBA, he was a nice defensive piece for Minnesota, who sported one of the best defensive units over the past several years during the 2023-24 season - a massive part of the reason they were able to upset the defending champion Nuggets on their way to a berth in the Western Conference Finals.

When you lose a perimeter defender like Tatum and the active hands of Holiday, a guy like Minott is the perfect body type to help fill those gaps.

Even with defense being a big part of Minott’s game, he told the media at camp that he’s being taught things defensively in Boston that he hadn’t been taught playing anywhere prior.

White was asked on Friday about what that unique defensive coaching looks like from his perspective having also spent time with other organizations.

“Just a little bit more detail,” said White. “At times, just get a stop. And then now we're trying to teach the little things that maybe they haven't heard before.

“So for me, I guess it's probably that I've heard it before [since being here]. But just trying to teach a little things to get an advantage and up the pressure.”

Replacing four massive pieces on defense is nearly impossible. But adding Minott to the mix will, at the very least, keep things feisty as Boston looks for its footing early in the season.

Celtics open day four of training camp on Saturday.

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.