The new season of Major League Baseball is here, and Opening Day looks much different than it did last year.

At the beginning of the 2020 season — a season delayed and shortened by the Covid-19 pandemic — fans were replaced by cardboard cutouts in the stands.

Now the majority of teams are opening their seasons with stadiums at 20% to 30% capacity, allowing fans to socially distance from one another.

"Baseball fans bring so much energy to the park, and our game is so much better with that passion in the stands," MLB Commissioner Rob Manfred wrote in an open letter to fans. "We are hopeful that hearing the sounds of a ballgame in-person represents important progress towards a 2021 that looks and feels closer to normalcy."

All 30 teams were supposed to begin play on Thursday, but Covid-19 has already caused one game to be called off. The Washington Nationals' home opener against the New York Mets was postponed due to Covid-19 issues within the Nationals organization.

An excited fan poses for a photo outside Wrigley Field in Chicago.
An excited fan poses for a photo outside Wrigley Field in Chicago.
Kamil Krzaczynski/USA Today Sports
Fans take in the Milwaukee Brewers' home opener.
Fans take in the Milwaukee Brewers' home opener.
Michael McLoone/USA Today Sports
A Yankees fan has his temperature checked before entering the stadium on Thursday.
A Yankees fan has his temperature checked before entering the stadium on Thursday.
Timothy A. Clary/AFP/Getty Images
Cleveland's Shane Bieber throws a first-inning pitch to Detroit's Miguel Cabrera, who homered to right field. The game in Detroit started with snow flurries.
Cleveland's Shane Bieber throws a first-inning pitch to Detroit's Miguel Cabrera, who homered to right field. The game in Detroit started with snow flurries.
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Mark Batie Jr. wears a tiger head at Detroit's home opener.
Mark Batie Jr. wears a tiger head at Detroit's home opener.
Carlos Osorio/AP
A fan holds a sign outside of Coors Field in Denver.
A fan holds a sign outside of Coors Field in Denver.
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Fans are spread out in Philadelphia.
Fans are spread out in Philadelphia.
Matt Slocum/AP
The Phillie Phanatic, the iconic mascot of the Philadelphia Phillies, is seen on a sign urging fans to "mask up" at Citizens Bank Park.
The Phillie Phanatic, the iconic mascot of the Philadelphia Phillies, is seen on a sign urging fans to "mask up" at Citizens Bank Park.
Rich Graessle/Icon Sportswire/Getty Images
Colorado's C.J. Cron collides with Los Angeles Dodgers catcher Austin Barnes after sliding safely into home.
Colorado's C.J. Cron collides with Los Angeles Dodgers catcher Austin Barnes after sliding safely into home.
Justin Edmonds/Getty Images
An usher cleans the seats before the Chicago Cubs hosted Pittsburgh at Wrigley Field.
An usher cleans the seats before the Chicago Cubs hosted Pittsburgh at Wrigley Field.
Nuccio DiNuzzo/MLB Photos/Getty Images
Fans sit in socially distanced squares during a game in San Diego.
Fans sit in socially distanced squares during a game in San Diego.
Denis Poroy/AP
Phillies star Bryce Harper waves to fans before the start of the first inning.
Phillies star Bryce Harper waves to fans before the start of the first inning.
Bill Streicher/USA Today Sports
Artists Kyle Banister, left, and Eric Matelski paint a mural near Coors Field in Denver.
Artists Kyle Banister, left, and Eric Matelski paint a mural near Coors Field in Denver.
Isaiah J. Downing/USA Today Sports
Fans catch a home run hit by Yankees slugger Gary Sanchez.
Fans catch a home run hit by Yankees slugger Gary Sanchez.
Chris Pedota/USA Today Sports
The late <a href="index.php?page=&url=http%3A%2F%2Fwww.cnn.com%2F2021%2F01%2F22%2Fus%2Fgallery%2Fhank-aaron%2Findex.html" target="_blank">Hank Aaron</a> was honored before the home opener in Milwaukee. Aaron, the longtime home run king and one of the greatest players of all time, died in January.
The late Hank Aaron was honored before the home opener in Milwaukee. Aaron, the longtime home run king and one of the greatest players of all time, died in January.
Aaron Gash/AP