They opened the gates on Thursday, six months after the end of a brief and surreal regular season played before cardboard cutouts and empty stands. Opening day for 2021 brought none of the usual standing-room-only crowds; with limited capacities, the games looked more like sleepy gatherings in mid-April. But the buzz was authentic, and there’s nothing like the real thing.

The first home run of the new year sliced through swirling snow flurries in Detroit. It was so confusing that the hitter, Miguel Cabrera — who is quite familiar with home runs, having swatted 488 in his career — slid into second on his trip around the bases, thinking he had hit a double.

A few players wore masks on the field, like the Brewers’ Lorenzo Cain, who opted out of last season after a few games, and the Philadelphia Phillies’ Didi Gregorius, who has a chronic kidney disorder. Cain scored the winning run in the 10th inning for Milwaukee, and Gregorius drew an intentional walk in the 10th for the Phillies, setting up Jean Segura’s game-winning single and bringing joy to the 8,529 real, live people on hand.

“So much better, so much better — that’s how it should be,” Phillies starter Aaron Nola said. “Hopefully it’ll be more soon, but it was good to hear humans in the stands.”

With more than 34,000 seats empty, though, there were ever-present reminders of the pandemic, like static intruding on a clear signal.

Most sobering was the postponement of the Nationals’ opener, against the Mets in Washington, after a Nationals player tested positive for the coronavirus. Because several teammates and a staff member were found to have been in close contact with the player, Major League Baseball said the teams would not open on Friday, either.

Then again, even without the virus-related postponement, Thursday was bound to be less than complete. The reason was the most mundane, and perhaps the most predictable, of all: bad weather in the Northeast.

With rain forecast, the Boston Red Sox announced at 9 a.m. that they had called off their opener with the Baltimore Orioles. The teams will try again on Friday afternoon, weather — and coronavirus test results — permitting.