He sees immaturity. He sees missed opportunities. Now, he sees a chance to get it right.
The Chicago Bears started offseason workouts this week, and for all the talk about how explosive he and Jay Cutler were when they played together in Denver, Marshall views things a little differently.
"When I look at film now, I think we were terrible," he said Wednesday.
Seems hard to believe. After all, the numbers during their three seasons together in Denver were nothing short of eye-popping.
There was Marshall earning the first of three Pro Bowl invitations in 2008 after finishing with more than 1,200 yards receiving for the second straight year. Cutler had his most productive season with a career-high 4,526 yards in his final season there, and the offense ranked second that year.
Sounds good, right?
"We were just young and immature out there on the field, not understanding the big picture of the offense and the game itself," Marshall said. "To see where we're at now, where our football mind is now, it's going to be really dangerous. I'm excited to really fall into this offense with a new mind."
Marshall was their biggest prize in a busy offseason, and they believe they're poised to make a run after two big season-ending injuries derailed them last season.
First, Cutler broke his right thumb and then running back Matt Forte sprained the medial collateral ligament in his right knee. What was shaping up as a playoff season ended in a tailspin that left the Bears 8-8 and cost general manager Jerry Angelo his job.
That certainly wasn't what the Bears had in mind after making the NFC title game the previous year. Now, they're aiming high again, and a big reason for that is the 6-foot-4 Marshall.
"He's a guy that I've missed," Cutler said. "It's good having him back. He's a little bit different guy than he was in Denver, in a good way. He's a really good influence for those younger guys."
The Bears believe that Marshall will take some of the pressure off Earl Bennett, Devin Hester and maybe even Johnny Knox, if he returns from a gruesome back injury. Knox insisted Wednesday he'll play again. He's just not sure when, exactly.
Knox hopes to be ready for the opener even though he realizes he could miss a big chunk of the season - if not all of it - after the injury during the game against Seattle in December. He said he's lifting weights on machines, riding bikes and jogging. He's in no hurry, though.
"There's really no timetable," Knox said. "We're all taking our time on this. I'm taking my time. I'm just focused on rehabbing right now."
He had just caught a pass when Seattle's Kam Chancellor poked the ball out of his hands. As Knox made a diving attempt to retrieve it, he got bent backward on a hit by Anthony Hargrove, leaving him with an injury that required surgery to stabilize a vertebra in his back.
He spent more than two months in a brace and lost 30 pounds after the operation. He said he has since gained 10 pounds to 165, and is pain-free. But clearly, he has a long way to go.
"I want to get back out there at the beginning of the season," said Knox, who hasn't seen a replay of the hit. "But who knows? We'll see how that turns out."
The offensive line remains a question mark. Forte's status remains up in the air, with the team slapping the franchise tag on him. But the Bears settled several big issues in a busy offseason.
New general manager Phil Emery solidified the backup quarterback spot by signing Jason Campbell from Oakland and added to the backfield by signing former Raiders running back Michael Bush.
But the biggest hole? They believe they filled it when they acquired Marshall.
Cutler now has a big target - two, actually, with 6-foot-3 rookie Alshon Jeffery in the mix - and that's something the Bears sorely lacked.
"It changes things - where you can throw the ball, when you can throw the ball," Cutler said. "Those guys are getting better and better each day. Devin Hester I think is probably having the best camp of all the receivers. So we've got a lot of weapons."
Notes: The Bears agreed to a one-year deal with DT Nate Collins. He appeared in 13 games over the past two seasons with Jacksonville. ... Chris Williams was splitting reps at left tackle with J'Marcus Webb, last season's starter. ... Marshall had high praise for Hester, saying, "I honestly think he's going to have an All-Pro year this year at wide receiver, and I'm just going to ride along and enjoy it with him."