Photo: Maddie Meyer (Photo)

Game 1 of the Eastern Conference Finals was never close. The Celtics went on a 17-0 run in the first quarter, and that was that. The central question of this series is whether Boston’s impressive team defense will be able to slow down a Cavs offense that ranked number one in the NBA in offensive efficiency after the trade deadline; at least on Sunday the answer was hell, hell, hell yes.

Brad Stevens elected to start Marcus Morris today for the defensive matchup with LeBron James. Morris, in the runup to the game, described himself as “the best guy defending [LeBron] in the league, outside of Kawhi [Leonard].” Whether that is ultimately true or not, Morris did a hell of a job Sunday afternoon, and he and the Celtics held LeBron to just 15 points on 17 shots, plus seven turnovers. LeBron had eight turnovers in the entire Raptors series. No Cavs player got loose against the Celtics, and just one Cavs lineup that played at least three minutes managed to outscore the Celtics. That was a goofy Jordan Clarkson-Rodney Hood-Jeff Green-Cedi Osman-Tristan Thompson group that shared the floor for a few minutes of late garbage time. The Celtics led by double digits for the final 42 minutes and 17 seconds of the game. It was a bloodbath.

Boston’s offense hasn’t been great all season, and 108 points isn’t a ton, but a full 60 of those points came in the paint, something Ty Lue pointed to in a terse and grouchy post-game presser as a sign of Cleveland’s lack of intensity:

The Celtics got efficient scoring from all of Morris, Al Horford, Jayson Tatum, and Jaylen Brown, who combined for 80 points on 61 percent shooting, and sizzling 10-of-18 shooting from beyond the arc. The real issue is less Boston’s offensive efficiency than it is the alarming 83 points put up by the Cavs. They’ll have to find a way to get going in Game 2 against a Celtics squad that is now 8-0 at home in these playoffs. It’s obviously too early to describe the shape of this series, but this was for sure an ugly wakeup call for the Cavs, and more evidence that these scrappy Celtics can out-execute and overwhelm anyone.