Two weeks ago, in a pregame media scrum at shoot-around, Al Horford called himself an elite shooter, which drew a laugh from a reporter.

Later that night, Horford went 5-of-7 from 3-point range in a Game 3 win over the Sixers in the second round. The pregame clip went viral, and Horford seemingly had the last laugh.

But with the Celtics falling into an 0-2 hole to start the Eastern Conference Finals, no one is laughing. Especially Horford, who is 1-of-8 from 3-point range in the series and shooting 27.7% from deep since his comments.

Celtics coach Joe Mazzulla addressed Horford’s struggles during a video conference with reporters Saturday, with a critical Game 3 win hours away.

“Al just has to continue to shoot the ball with confidence when he’s open,” Mazzulla said. “He’s been one of our better shooters throughout the year, and when he’s playing well, he gives us a great opportunity on the offensive end. Defensively, he’s been very, very solid.”

Mazzulla started Horford and Robert Williams together for a second straight game Friday night, though the Celtics’ top bigs played just five minutes together, the shortest time any Boston duo in Game 2, per NBA tracking data.

Why was that?

“Just looking at how our switching attack can be better,” Mazzulla said.

He later added: “Trying to generate those matchups, and from the defensive end just looking to guard their shooters and do the best we can in the half-court.”