When Patrice Bergeron returned from injury during the Maple Leafs series, he made the Bruins better. But I wouldn’t say he was the difference. Too many hockey players participate in playoff games (20-22) to connect the dots through any non-goaltender (unless that man’s name is Gretzky or Crosby). Basketball is different. The playoffs typically shorten any team’s bench to 7-9 guys. I don’t see the Celtics losing this series to the Bucks if Marcus Smart is able to play.

Smart tore a tendon in his thumb six weeks ago. Kyrie Irving went in for the first of two knee surgeries three weeks later. Irving is clearly the best player on this team. Without him, the Celtics aren’t good enough to make The Finals this season, much less win them.

But Smart’s return should win the Celtics this series and perhaps the next. He’s that good, that influential, and it’s sort of amazing how far under the radar he manages to fly.

When the playoffs started, national media and the talking heads on ESPN and TNT made a big deal about how Boston would contest these playoffs without two starters, Irving and Gordon Hayward. But the latter has been gone so long (having gruesomely wrecked his ankle in the season opener), it honestly doesn’t feel anymore like we’re playing without him. In theory, Hayward is a stud, exactly the sort of wing shooter the Celtics need. But he was a brand new free agent signing back in October. He might have taken Boston to the next level but we really don’t know for sure. [One thing is for sure: If he had played this season, Jayson Tatum and Jaylen Brown would not have progressed as far as they have. The minutes and end-of-game possessions would not have been there for them.]

But too many folks missed the fact that Boston opened these playoffs without three starters, because Smart is one of the five best guys on this team and the best all-court defender in the NBA. He might not have started every game, but he finished every game (that mattered). Without Irving and Hayward, Boston will always struggle to score down the stretch. But with Smart guarding the other team’s best player (a role he routinely occupies), with Smart representing a massive upgrade over plucky-but-limited Shane Larkin in the guard rotation, the Celtics are a different team.

There is no one in basketball quite like Marcus Smart, and I’m not sure why the rest of the league fails to appreciate this fact. He is the best defender on the league’s top defensive team but garners no laurels. He wasn’t even named to the All-NBA Defensive Team last season, when he was healthy. See here that list of 10 honorees from 2016-17:

1st Team

Chris Paul

Patrick Beverly

Kawhi Leonard

Draymond Green

Rudy Gobert

2nd Team

Tony Allen

Danny Green

Anthony Davis

Andre Roberson

Giannis Antetokounmpo

This is a pretty fair representation of top NBA defenders for 2017-18, as well, but Chris Paul and Tony Allen are shadows of the defenders they were 5 years ago. Beverly and Kawhi have been hurt all this season. Roberson has been out since January and is a complete offensive liability. Danny Green? He blocks it well for a 3, but otherwise I don’t know what he’s doing on this list. Draymond, Gobert, Anthony Davis and the Freak are superb defenders — as big men. They are a particular type of defensive asset; they are not all-court defenders.

Once we remove the big men, I would take Marcus Smart over any of the remaining six guys. Of those who are injured, only Kawhi compares. At 6’4” Smart can check your point guard, your shooting guard, your small forward and most of the league’s 4s. He routinely guards LeBron James and drives him crazy. He is perhaps the only guy in the league to get inside James Harden’s head.

There is no one quite like Marcus Smart playing in today’s NBA. I’ve been singing his praises for several hundred words now, but I haven’t even detailed his best qualities: He’s wicked smaht. In fact, he’s flat-out smarter and more competitive than anyone in the game, with the possible exception of LeBron — who is so good, he allows his competitive nature to flag on occasion. Marcus never does.

He is not without fault. Marcus is not a good shooter — a reality underlined by the fact that he refuses to acknowledge it. Though he shot just 37 percent from the floor this year (30 percent from 3), Smart never hesitates; he shoots with the confidence of Bradley Beal — which makes me love the guy even more.

Like I said, the Celts aren’t going to The Finals this year. Ultimately, while injuries have catalyzed the development of Brown, Tatum and Terry Rozier (which bodes well for next June), Boston doesn’t have the horses to play for a title this June. But with Smart back and Brad Stevens pulling the strings, they’ll beat the Bucks — probably tonight.