RENTON — The Seahawks have a new, big, accomplished pass catcher for offseason workouts.

The team officially announced Wednesday before taking the practice field for another workout of organized team activities the signing of six-time Pro Bowl wide receiver Brandon Marshall.

To make room on the 90-man offseason roster, Seattle waived undrafted rookie fullback Marcus Martin. Martin, from Slippery Rock, signed earlier this month.

Marshall keeps his familiar NFL jersey number 15 with the Seahawks. Recently signed wide receiver Keenan Reynolds, who was 15 last week, is number 85 now.

As Marshall wrote on his Instagram post Tuesday announcing he was becoming a Seahawk: “Let’s Go.”

The Seahawks will begin seeing over the next week and a half of OTAs, the mandatory veteran minicamp June 12-14 and training camp that begins July 26 how recovered the 34-year-old Marshall is from the severe ankle injury that ended his only season with the New York Giants last year after just five games and a career-low 18 catches.

The 12-year veteran has six seasons with at least 100 receptions.

He’s here because of his size. The Seahawks love how big he is so much they

Marshall was an All-Pro in 2012 for catching 118 passes for 1,508 yards for the Bears. He had 109 receptions with a league-leading 14 touchdowns in 2015 with the New York Jets, then 59 for them in 2016 before he played only a month last season before getting injured with the Giants.

He arrives six weeks after the Giants waived him with a failed-physical designation.

“We would always like to have (big wide receivers),” Seahawks coach Pete Carroll said this month. “Our guys that do a lot of our playing are the quicker guys, smaller guys … so we are always looking.”

Seattle becomes his sixth team in 12 NFL years, after Denver, Miami, Chicago, the Jets and the Giants. The Seahawks were believed to be the only team interested in signing Marshall after the Giants gave up on him April 19.

The team mentioned at the end of its announcement Wednesday that Marshall was diagnosed with borderline personality disorder in 2011 and that he has co-founded PROJECT 375, a non-profit that is dedicated to the education, support and treatment of mental health. Since its founding, PROJECT 375 has raised more than $1.6 million while also bringing awareness to mental health issues.