List of Major League Baseball mascots

This is a list of current and former Major League Baseball mascots, sorted alphabetically.

The tradition in the Major League Baseball mascot began with Mr. Met, introduced for the New York Mets when Shea Stadium opened in 1964. Although some mascots came and went over time, the popularity of mascots increased when The San Diego Chicken started independently making appearances at San Diego Padres games in 1977. Philadelphia Phillies management felt they needed a mascot similar to the Chicken, so they debuted the Phillie Phanatic in 1978.

Today, all but three major-league teams have "official" mascots (Dodgers, Yankees, and Angels). Three team mascots — the Phillie Phanatic, Mr. Met, and Slider (Cleveland Indians) — have been inducted into the Mascot Hall of Fame. Several others have been nominated since the Hall's creation in 2005.

Ace is the official mascot of the Toronto Blue Jays. He, along with his female counterpart, "Diamond" replaced former mascot BJ Birdie before the 2002 season as a mascot duo. Like his predecessor, Ace resembles a large blue jay. The mascot's name is baseball slang for a team's top starting pitcher (the "ace" of the staff, such as former Blue Jays pitcher Roy Halladay).

In 2004, Ace became the sole mascot of the team after Diamond was removed by the Blue Jays prior to the start of the season. In 2011, Blue Jays fans were introduced to his younger brother Junior (see below).

Barrelman (aka "Owgust" and "Beer Barrel Man"), is an auxiliary mascot for the Milwaukee Brewers. He was resurrected an upgraded to be a costumed performing character in 2015, having previously only been an official logo image and since 1977 only appearing on special materials.

...
Wikipedia