He played in the opener through sheer athleticism and ability. He was productive all season, but did not have the type of year that he could have produced without an unsettling offseason.
One year later, Maclin is back to who he's supposed to be, ready to play in Sunday's opener against the Cleveland Browns. He has added 10 pounds of muscle. He can smile without worry. And he speaks with a perspective that belies his age, because once imminent death is a possibility, third and 12 against a disguised coverage becomes less daunting.
"You cherish life more," Maclin said. "You cherish the things that are outside of football, and you cherish football more. It makes you realize this really is a gift. And not because you're good at it, but because without the other things that go on, this wouldn't be possible."
Life would seem to be grand for Maclin. He's 24 and on the cusp of NFL stardom, already with a $15.5 million contract and potentially a more lucrative one if the season goes as planned.
And life is good for Maclin, although not for the reasons it may seem. Maclin's story has become well-known and oft-told: tough upbringing before being adopted by a family, college star who overcame injury to become a first-round pick. Then add in last summer's experience, when he waited to learn if he had lymphoma, if he'd play football again, if he'd live to see 24.
But it's the next chapter of the story that matters now. He's still breathing and still playing and might soon be starring, and Maclin is ready for what will happen next.
Much of the focus leading up to opening day last year was whether Maclin would be able to play. It was a game in front of family and friends in his native St. Louis. Simply reaching the game seemed like an achievement. But just showing up for the opener is not enough this season.
"There's none of that," said Isaiah Mares, Maclin's close friend since childhood who is now his business manager. "It's a career year. He can step out and do everything he wants to accomplish, because there are no setbacks. There are no excuses."
For a wide receiver, the third season is often the season that determines whether he'll become a frontline player. Of the 17 NFL receivers who surpassed 1,000 yards last season, 13 reached that mark by or before their third season - and only two of the remaining four did it with their original team.
Maclin, a productive Eagle the last three years, has never topped that plateau. He finished with 964 yards playing in 16 games in 2010, and totaled 859 yards last season in 13 games. If not for hamstring and shoulder injuries that sidelined him in November, Maclin likely would have reached that mark. But he is still not considered among the NFL's top receivers, even if his talent and role suggest he should be.
"As long as we're successful winning games," Maclin said, "I'm sure my numbers will be up there."
Although his illness did not keep him out at any point in 2011, it prevented him from entering the season with the necessary training and conditioning. Eagles wide receivers coach David Culley said Maclin's illness "definitely had an effect on him early [in the season]." Culey noted that Maclin never thought he was hindered, but there was a noticeable improvement in Maclin's conditioning later in the season.
"What happened, happened, and there's nothing we could do about that," Culley said. "At the end of the year, he was playing the way we felt he was capable of playing. But he didn't have the complete year that you would have liked to have seen from a guy that had gone through the offseason, had gone through the training camp. His numbers would have been more."
Culley said Maclin is capable of a breakout season, although he added that it's difficult to do so in the Eagles' offense, with the ball spread around so much. But 1,000 yards is reachable, and that number would indicate Maclin has taken the next step in his development.
The better Maclin plays, the more likely a new contract would be on the way. Maclin is signed through 2013. The Eagles are often active in signing young talent to contract extensions, and LeSean McCoy, who was in Maclin's draft class, already has received a new deal. McCoy had one less year on his rookie contract, so there was more of an impetus, but he also proved he was one of the top players at his position.
The Eagles could be motivated to act quickly to secure Maclin, who wants to stay in Philadelphia and is a vital part of the offense. Just don't expect Maclin to publicly ask for one - or let the lack of a long-term deal affect his season.
"As soon as I start [thinking about a contract], that's a distraction I don't need," Maclin said. "I've done all the right things and handled myself on and off the field. When the time comes, hopefully it comes as smooth as it can."
Maclin turned 24 in May, and a reminder of that made him smirk. He believes he's more mature than his age would suggest.
"I feel a lot older than that," Maclin said. "I don't think the average 24[-year-old] has seen what I've seen or been through what I've been through."
The takeaway is trying to, as he said, find appreciation for "every breath." Mares said Maclin has verbalized this sentiment and acts with greater urgency. Maclin commits significant time to charity, whether it's youth football camps in New Jersey and Missouri, helping 200 underprivileged families in St. Louis with back-to-school packs, or serving as a spokesman for the National Adoption Center. The vulnerability he experienced has created an initiative and provided balance.
"I think he really does see football as a privilege at this point," Mares said. "There honestly was a time when he never thought he'd play football again, so that puts everything in perspective, and that goes into everything he's doing with his job and his life overall."
Jason Avant, the elder statesman in the Eagles' wide receivers room, has also noticed the maturity. Avant said Maclin was never arrogant, but he developed a humility after last summer. There are fewer mumbles and no complaints. Avant called it a "mind-set of appreciation."
For Maclin, the key has been accountability. He said a 15-yard out pattern must be run at precisely 15 yards - not 14, not 16. The minutiae should be embraced, not dismissed.
"I don't want to be a disappointment to anybody," Maclin said. "I want to be there for my family. I want to be there for my friends. I want to be there for my teammates. The fact that, if I let anybody down, that would be my biggest worry."
But Maclin stops and makes sure it's known that everyone has his own story, and the motivation that drives him. It just so happened that he suffered his scare when he was 23, and he has an occupation that made that scare public.
He knows nothing is guaranteed, but on Labor Day 2013, Maclin doesn't expect to be talking about his illness like last season, or the possibility of experiencing a breakthrough season, as he did last week. He wants his story to change again.
"Between this time, today, and next year, hopefully we have a Super Bowl," Maclin said. "And hopefully I'll be a contributor in that."
Contact Zach Berman at firstname.lastname@example.org, or follow on Twitter @ZBerm.