''Let's not jump ahead. I've got a lot of learning to do and a lot of catching up,'' Marshall said after his first practice with New Orleans on Wednesday. ''I've been at the top and I'm on the bottom right now.''
By bottom, the 34-year-old Marshall means getting cut repeatedly in the past couple seasons, most recently by Seattle a couple weeks ago.
Even after he worked out for New Orleans (8-1) last week, Marshall wasn't the Saints' top choice. New Orleans went instead with Dez Bryant, but lost the former Dallas Cowboys star to a season-ending Achilles injury in his second practice.
''When you're on the other side of 30 and you don't produce, this is the situation you'll find yourself in,'' Marshall said. ''Being cut two times in a year is interesting. It built a lot of character. ... When Seattle cut me, I just continued to work out, stay in shape and have faith.''
Marshall had flown back to his temporary home in Seattle after his Saints tryout, only to hop back on a flight to New Orleans again on Sunday afternoon, while the offense he was about to join was putting up 51 points in Cincinnati.
Ankle and toe injuries cost Marshall most of his 2017 season with the New York Giants, who didn't bring him back, leaving him free to sign with the Seahawks. Marshall said he wasn't full healthy until around Week 3 or 4 of this season which, ironically, was about the time his snap count began to plummet in Seattle.
''I know that the narrative is that I'm done,'' Marshall said.
Yet Marshall predicted he'd demonstrate in practice that between his 6-foot-5 frame, route-running, strong hands, and ability to quickly grasp offensive schemes, that he can still help a team with playoff credentials. Marshall noted that because he played in Chicago under then-offensive coordinator Aaron Kromer, a former offensive assistant to Saints coach Sean Payton, he is familiar with New Orleans' scheme.
Payton called Marshall's ability to process a play book ''one of his strengths,'' adding that he expects Marshall's transition in New Orleans ''to be pretty smooth.''
Meanwhile, Marshall described the opportunity to play with Saints record-setting QB Drew Brees ''a wide receiver's dream.'' Likewise, Brees was quick to throw a few compliments Marshall's way.
''He's a smart, veteran guy who is very fluid. I've seen him in a lot of different offenses - seen him be successful both as an outside receiver, an inside receiver. He's very versatile. He's a big target. A big catching radius. Just watching him run today, he's pretty impressive.
''We talked for a while today,'' Brees added. ''He's excited. We're excited to have him.''
Marshall's addition adds depth to an offense that already leads the NFL in scoring with 36.7 points per game and ranks in the top five in yards per game with 413.9.
Seattle released Marshall on Oct. 30 after he'd appeared in the first seven games this season, catching 11 passes for 136 yards and one touchdown. But he had just two catches for 16 yards in his last four games.
Seattle was the sixth NFL team for Marshall, who has eight 1,000-plus-yard seasons in his career. His best season, statistically, came with the New York Jets in 2015, when he caught 109 passes for 1,502 yards and 14 touchdowns.
Even now, Marshall insisted, his motivation remains to achieve ''greatness.''
''There's no reason why, with technology and modern medicine and with access we have to doctors around the world, why athletes can't play into their mid-30s or their 40s,'' Marshall said, stressing that he now feels ''fit as a fiddle and healthy as a trout.''
It's not yet clear whether Marshall will play much, if at all this Sunday against Philadelphia. But Eagles coach Doug Pederson said his defense has to be prepared for the possibility.
''He's, I think, a red-zone threat with his size and so I think that's where we'll see him a little bit, is down there,'' Pederson said. ''He's another big, physical receiver, hard to defend and our guys definitely have their work cut out this week.''
Notes: Starting left tackle Terron Armstead did not practice. He was listed on the injury report as having a shoulder injury. Veteran Jermon Bushrod is filling in, resuming the role he occupied on New Orleans' 2009 Super Bowl championship squad.
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