10:09 AM PT -- The Miami Marlins tell TMZ Sports ... “This was a regrettable exchange by our otherwise creative social media team. Unfortunately, in this medium, sometimes we swing and miss, and this was definitely a miss.”
9:54 AM PT -- The Marlins just posted an apology for the insensitive tweet ... saying "Hi, guys. Like everyone who grew up watching him, we miss Steve. We’re so sorry to have made light of his passing."
The tweet has NOT been deleted.
What. In. The. Actual. Hell.
The Miami Marlins CROSSED THE LINE in a stupid Twitter spat with the Tampa Bay Rays ... saying, "YOU'RE LITERALLY THE ANIMAL THAT KILLED STEVE IRWIN."
So, why the hell would a Major League Baseball team invoke the name of a global treasure who was tragically killed by a real-life stingray in 2006???
Here's the backstory ...
The Marlins played the Rays on Saturday -- and even though Miami lost, they posted a highlight showing right fielder Brian Anderson GUNNING a guy out at the plate in the 8th inning.
The Tampa Bay Rays social media team responded to the tweet saying, "Show the final out." Quality burn.
Miami responded -- taking a shot at Tampa Bay over possible plans for the Rays to become a 2-city team, splitting time between TB and Montreal.
Tampa Bay responded by essentially pointing to the score board ... prompting Miami to send the most savage tweet in MLB history.
"yOU'RE LITERALLY THE ANIMAL THAT KILLED STEVE IRWIN LOG OFF."
Tampa Bay -- which won both games of their 2-game series with Miami -- fired back, "You're literally the team that just got swept, log off."
Of course, Irwin -- aka "The Crocodile Hunter" -- was killed at age 44 when he was pierced in the heart by a stingray barb while filming an underwater documentary.