Buck Showalter took in “The Music Man” last week, but the Mets manager saw a far better show Saturday.

An announced crowd of 43,857 sat in their seats at Citi Field, then rose once the first strings of “Simple Man” filled the stadium. Jacob deGrom, the best pitcher in the world, took the mound for a third time this season and second time at home. The combination of a superstar with stuff that has never been seen before and the fact that stuff has been rarely seen over the past few seasons because of a litany of injuries adds an element of urgency. Fans want to savor every moment of deGrom.

That crowd — the largest since 2019 and ninth biggest regular-season crowd in the stadium’s history — saw six crisp, dominant innings with 10 strikeouts from the ace. Seth Lugo and Trevor May formed the bridge to Edwin Diaz, who himself is quite literally a show.

SNY has begun turning his entrances into cinema, adding some black-and-white flair to Diaz’s emergence from the bullpen Saturday. He is not just an All-Star with an untouchable slider but a spectacle worth the price of admission. Citi Field turns into a trumpet-filled club for a few minutes, and many of the fans don’t even return to their seats. On Saturday, they stood, they cheered, they watched as a strikeout artist who has not allowed a run in his past 20 appearances got the job done again in a 1-0 win over the Phillies.