The problem with the 2023 Boston Celtics can be summed up in one quote: "So, definitely learned from that."
That fragment speaks to the disservice the Celtics did not only to their superstar young core of Jaylen Brown and Jayson Tatum, but to the man who uttered those words on Monday.
Joe Mazzulla isn't ready and it has never been more clear. The playoffs are no place for a head coach to be learning lessons as basic as, "call a bleeping timeout," at least not when you're piloting the best team in the Eastern Conference with a wide-open lane to the NBA Finals if you can just keep from careening off the road.
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The Celtics are instead disintegrating at the worst possible moment, and their tight-jawed, jiu jitsu-tossing head coach appears helpless to stop it.
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On Tuesday, the Celtics came out tighter and flatter than hospital corners. They fell behind by 14 and basically stayed there the rest of the night in a 115-103 Game 5 loss that sends them to Philadelphia on the brink of elimination in a series that might otherwise already be over.
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The Celtics admitted to taking the Sixers lightly without MVP Joel Embiid in Game 1, handing a gift to James Harden and Co. that they sure could use right now. Their lack of focus was inexcusable.
After breezing to victories in Games 2 and 3, which is primarily how they win, they dug a huge hole in Game 4, only to force overtime and seemingly have victory in hand, at least until Mazzulla's ill-timed teachable moment.
With 19 seconds left and the Celtics trailing by a point because one of their All-Stars had picked an inopportune time to abandon Harden in the corner, Mazzulla watched the shot clock reach zero without a shot reaching the basket. If he could do it again, he said, he would've called timeout.
That's a horrific way to learn such a rudimentary lesson, but it's what happens when you entrust one of the league's most mercurial rosters to a 34-year-old rookie coach hired under duress.
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Mazzulla never should've been near the sideline of a defending finalist – he actually spent last season not on the bench, but behind it – but the Celtics had few options after suspending Ime Udoka on the eve of training camp, especially since the other most likely internal candidate, assistant Will Hardy, had already left to coach the Jazz.
Mazzulla led the Celtics to 57 wins, but after a 21-5 start, his team floundered while never quite finding the gear that propelled it to last year's Finals.
These Celtics operate as efficiently as a kinked bicycle chain, unable to compete one clean revolution before practically flying over the handlebars. Put another way, they're perpetually one discordant note shy of a symphony.
Their lack of cohesion was evident Tuesday, when the Sixers got whatever they wanted in the pick-and-roll on one end, while the Celtics flailed helplessly on the other. They played like a team that has accepted it will either make a bunch of 3s in the first quarter or head home for the summer.
Making matters worse, Mazzulla is being outclassed by veteran Doc Rivers, who's beloved for leading the Celtics to the 2008 title, but objectively isn't a great playoff coach.
Despite leading loaded teams in Boston, Los Angeles, and Philly, Rivers barely owns a .500 postseason record, and his three conference finals trips in green are the only ones of his 24-year career. It brings no joy to say this, but it's not as if Mazzulla is being outfoxed by Eric Spoelstra, Gregg Popovich, or Steve Kerr, proven title winners many times over. Rivers's postseason record is decidedly mixed.
But then again, Doc has been around long enough that he cut his teeth in the early 2000s with the Magic during their period between franchise centers Shaquille O'Neal and Dwight Howard. He figured out how to coach before he was anywhere close to winning a championship.
That's how it's supposed to work. Rookie coaches either take their lumps with a non-contender, or they apprentice for a decade as assistants, a la Spoelstra and Udoka. Otherwise, they're forced to learn the kind of lessons that can cost you a title.