Cal Raleigh is called “Big Dumper” because the nickname is a joking reference to his notably large backside (butt), not because of anything he dumps on the field like home runs or trash talk.

Origin of the nickname

The nickname “Big Dumper” was coined by Raleigh’s former Seattle Mariners minor-league teammate, outfielder Jarred Kelenic, around 2020 when they were together at the club’s alternate training site during the pandemic season. Kelenic started calling him that because of his prominent posterior, and the name stuck in the clubhouse.

Kelenic later made the nickname public when he tweeted “Big Dumper” in reference to Raleigh’s promotion to the big leagues in 2021, which helped spread it among fans and eventually into national broadcasts.

MLB-wide fame in 2025

The nickname exploded into mainstream MLB conversation during Raleigh’s breakout 2025 season, when he hit a record-tying 60 home runs as a catcher and became a fan favorite in Seattle. TV announcers, including Yankees broadcaster Michael Kay, openly explained on air that “Big Dumper” comes from Raleigh’s “pretty large posterior,” leading to viral and awkwardly funny moments when cameras lingered on his backside.

Raleigh has since leaned into the nickname, joking about it in interviews and even signing his popular bobblehead on the butt when fans request it. The Mariners have embraced “Big Dumper” with merchandise and special All‑Star/Player’s Weekend gear, turning it into one of the most fun and recognizable nicknames in baseball today.

Reaction from Cal and his family

Initially, Raleigh admitted he wasn’t sure about the nickname, but as his performance and popularity soared in 2025, he’s fully accepted it with a sense of humor. He’s said it’s “a blessing and a curse” and joked that his big backside is just part of his strong, powerful lower half that helps him hit so many home runs.

On the other hand, his mom has said she thinks the nickname “stinks,” though she also appreciates the fans’ love for her son.

Trending context (early 2026):
“Big Dumper” is still widely used in MLB broadcasts, sports media, and social media when discussing Raleigh, especially in relation to Mariners’ gear and his home-run power. The nickname has become a cultural mini-phenomenon in MLB fandom, often cited as one of the best and funniest nicknames in the game right now.

Information gathered from public forums, sports media, and interviews available on the internet.