12:58 PM PT -- The Mets just commented on the suspension ... and say they are "extremely disappointed" over the positive test and subsequent ban.
"The violation is very unfortunate for him, the organization, our fans, and the sport," the team said in a statement.
"The Mets fully support MLB's efforts toward eliminating performance-enhancing substances from the game."
Robinson Cano has been popped for a banned substance again ... and this time, it'll cost him the entire 2021 season AND a fat paycheck.
The New York Mets star second baseman tested positive for PEDs, according to ESPN's Jeff Passan, and he's now been suspended for all of next year.
38-year-old Cano will also forfeit $24 MILLION in salary due to the season-long ban, Passan added.
The 8-time All-Star had previously been busted for using a banned substance back in 2018 ... when MLB hit him with an 80-game suspension.
At the time, Cano admitted to taking Furosemide -- which MLB has barred because it can act as a masking agent for PEDs -- but the baseball star claimed he did NOT use it for performance enhancement on the diamond.
"Furosemide is used to treat various medical conditions in the United States and the Dominican Republic," Cano said in '18. "This substance was given to me by a licensed doctor in the Dominican Republic to treat a medical ailment."
"While I did not realize at the time that I was given a medication that was banned, I obviously now wish that I had been more careful."
Unclear what Cano tested positive for this time ... but his absence next year will sure hurt the Mets.
Cano had a monster 2020, batting .316 and hitting 10 home runs in just 49 games.
Before the suspensions ... Cano was considered a Hall of Fame candidate -- with a career batting average of .303 and 334 total home runs.