By Matthew Geagan, CBS Boston

BOSTON (CBS) — The Celtics are a dangerous enough bunch when Kyrie Irving is scoring at will, Al Horford is doing his above average thing, and their dynamic youngsters Jaylen Brown and Jayson Tatum are looking like anything but 20-year-olds.

But now that their bench has rounded into shape, look out. Celtics reserves are not only taking pressure off their starting five, but crushing their opponent’s will in the process. Boston’s bench dominance continued in Thursday night’s victory over the Timberwolves, as Celtics reserves outscored Minnesota’s 42-20. Boston’s bench is averaging 51 points per game over their last three games, a small sample size, but the culmination of something big that has been brewing for some time.

Brad Stevens has found the right rotation, and it’s paying off in a big way. Leading the bench’s outburst on Thursday night was Boston’s pair of Marcuses, which could be a deadly duo come playoff time. Marcus Morris was unstoppable when he first checked in during the first quarter, turning the tides of a tight game by going on a personal 9-0 run. He finished the night with 17 points off 7-for-15 shooting and five rebounds, the kind of performance the Celtics envisioned from the forward when they acquired him from Detroit in the offseason. He not only lit up the scoreboard, but brought his signature grit on the defensive end as well.

Brad Stevens on Marcus Morris: “Marcus is a hard guy to guard at the 3 because of his size, and also at the 4 because he spreads the floor so much. He’s in a good groove right now.” — Boston Celtics (@celtics) March 9, 2018

Not to be outdone was Marcus Smart, who had a typical Marcus Smart evening. He didn’t fill up the stat sheet, and had plenty of missed shots with a 2-for-7 shooting line, but also provided his nightly handful of muscle plays that warm Tommy Heinsohn’s heart. Smart hit the floor on several occasions for loose balls and played the determined and physical defense that will earn him some big bucks on the restricted free agent market this summer.

It doesn’t matter if he’s D-ing up against a fellow guard or a bigger power forward; if Smart has a shot at the ball, he’s going to swipe it. More times than not, that leads to great things for the Celtics.

Though Smart only had nine points on the night, two of them were Boston’s loudest of the evening. The guard came out of nowhere to slam down a Tatum miss in the second quarter, another reminder of just how good Smart can be offensively when he actually attacks the basket.

With the two Marcuses leading the way on Thursday, Terry Rozier quietly put up 13 points in his 24 minutes, the 15th straight game the guard has scored in double digits. Boston’s bench is enjoying an embarrassment of riches lately, scoring 67, 44 and 51 points in their last three games, respectively, for their best stretch of the season. Though their 67 points last Saturday night in Houston didn’t result in a win, it’s what kept Boston afloat in that frustrating loss. It proved that even if Irving is struggling, the Celtics can put up a fight against the best of the NBA.

With their reserves playing above and beyond right now, the Celtics have returned to being a formidable threat in the Eastern Conference. Rozier not only provides a giant spark offensively, but with Smart to his side, gives the Celtics great defense from their backup guards. The unit has toughness inside with Morris, Greg Monroe and Daniel Theis. All of that takes pressure off the starting unit, who can now feel confident that the reserves will hold their own, which was not always the case for a large stretch of the season.

Whether or not the bench can keep this dominant stretch going remains to be seen, but after months of sorting things out, the Celtics have set roles and have settled on a rotation with the playoffs just over a month away. They can feel confident in throwing that relentless trio of Smart, Rozier and Morris out there and not miss a beat, and if it keeps up, they’ll be even more dangerous come mid-April, May, and June.