Robinson Cano has been suspended 80 games after testing positive for a banned substance, Major League Baseball announced on Tuesday.

The Mariners second baseman tested positive for furosemide, a diuretic better known as Lasix, which is often used to help mask banned substances in urine tests.

The suspension will begin right away, even though Cano is on the disabled list, due to a fractured hand he sustained being hit by a pitch on Sunday. He is not eligible for postseason play this season as a result of the suspension. The Mariners currently sit at 23-17, only 1 1/2 games behind the Astros and Angels in the American League West, 1/2 game behind the second AL Wild Card spot.

“We were disappointed to learn today that Robinson had violated the terms of Major League Baseball’s Joint Drug Prevention and Treatment Program. Our organization fully supports the program,” the Mariners said in a statement. “Robinson made a mistake. He has explained to us what happened, accepted the punishment and has apologized to the fans, the organization and his teammates.

“We will support Robinson as he works through this challenge.”

An eight-time All-Star, the 35-year-old Cano is hitting .287/.385/.441 with four homers in 169 plate appearances this season. He is fifth among active players with 2,417 career hits, and is in the fifth year of a 10-year, $240 million contract he signed with Seattle during the 2013-14 offseason.

“Recently I learned that I tested positive for a substance called furosemide, which is not a performance-enhancing substance,” Cano said in a statement issued by the MLB Players Association. “Furosemide is used to treat various medical conditions in the United States and the Dominican Republic. 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.”

“For more than 15 years, playing professional baseball has been the greatest honor and privilege of my life,” Cano said. “I would never do anything to cheat the rules of the game that I love, and after undergoing dozens of drug tests over more than a decade, I have never tested positive for a performance-enhancing substance for the simple reason that I have never taken one.

“Today I decided to accept MLB’s suspension. This was the most difficult decision I have ever made in my life, but ultimately the right decision given that I do not dispute that I was given this substance. I apologize to my family, friends, fans, teammates and the Mariners organization. I am extremely grateful for the support I have received during this process, and I look forward to rejoining my teammates later this season.”

A source told MLB.com’s Mark Feinsand that Cano has been tested at least once since the positive test occurred with nothing showing up on the test.