ST. LOUIS — Pirates center fielder Starling Marte on Tuesday was suspended for 80 games after he tested positive for Nandrolone, a performance-enhancing drug.

The suspension is without pay and is effective immediately.

Marte issued an apology via an email from the Players’ Association.

“I have been informed that I have tested positive in one of the tests that are regularly done in my job,” Marte said. “In this very difficult moment I apologize to my family, the Pittsburgh Pirates, my teammates, my fans, and baseball in general. Neglect and lack of knowledge have led me to this mistake with the high price to pay of being away from the field that I enjoy and love so much.

“With much embarrassment and helplessness, I ask for forgiveness for unintentionally disrespecting so many people who have trusted in my work and have supported me so much. I promise to learn the lesson that this ordeal has left me. God bless you.”

In a statement delivered via email, team president Frank Coonelly said the Pirates “fully support” MLB’s Joint Drug Treatment and Prevention Program.

“We are disappointed that Starling put himself, his teammates and the organization in this position,” Coonelly said. “We will continue to fight for the division title with the men who are here and will look forward to getting Starling back after the All-Star break.”

Over six seasons in the majors, Marte, 28, has a .288 batting average and a .789 OPS. This year, he is batting .241 with a .659 OPS, two home runs and stolen two bases.

The Pirates did not immediately indicate how they will make up for Marte’s absence. Andrew McCutchen, who this season was moved to right field, could move back to center.

Top prospect Austin Meadows is batting .162 after 10 games this year with Triple-A Indianapolis.

Rob Biertempfel is a Tribune-Review staff writer. Reach him at rbiertempfel@tribweb.com or via Twitter @BiertempfelTrib.