It's only natural to have some reservations about Lane Johnson after he was suspended for 10 games last season for his second violation of the NFL's performance-enhancing drug policy. One more positive test and the Eagles will lose their starting right tackle for two full years.
Fortunately, Johnson seems determined to avoid any future run-ins with the league. The 27-year-old changed his entire approach this offseason, cutting out negative influences or any other voices at all while preparing for the 2017 season.
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"I just trained by myself back in Oklahoma," Johnson said after the Eagles' first full-team practice of OTAs on Tuesday. "Trained by myself and everything went good. I came back, my body weight is about 325, so I'm heavier than I've ever been. I feel in good shape, and I have a lot to prove, so it's a big year for me.
"I did everything by myself. There wasn't going to be any mishaps."
Two suspensions totaling 14 games later, Johnson has gained a healthy fear of being unknowingly steered toward an illegal supplement.
Johnson tested positive for PEDs before the season last year after taking a banned substance known as peptides and was eventually slapped with the full 10-game penalty after a lengthy appeal process. The fifth-year veteran always maintained peptides were not listed on the label of the offending supplement.
Johnson filed a lawsuit against the NFL and the players' association in November after the suspension was upheld. Its status is ongoing.
Johnson also served a four-game suspension in 2014.
When he's not in trouble with the league office, Johnson is a vital cog in the Eagles' offense. They went 5-1 with him and 2-8 without him last season.
"I feel like whenever I'm playing, I try to be the best right tackle in the NFL," Johnson said. "My deal is to just stay on the field, play a complete season, and I think it will be a big year for me."
Johnson isn't concerned about losing a competitive edge, physically or mentally, after dropping supplements altogether.
"I've always been the athlete that I am," Johnson said. "That's what I'll continue to prove. I'm gonna go play and show people what I can do."
Signed in January 2016 to a five-year contract extension worth $56 million, Johnson has plenty to prove. He was working out in place of 35-year-old left tackle Jason Peters, who wasn't at the start of OTAs, on Tuesday and is expected to one day replace the nine-time Pro Bowl selection permanently.
Despite his checkered past, it sounds like Johnson knows exactly what's on the line, which is why he chose to go it alone this offseason. The only person you can trust is yourself.
Then again, Johnson still has his vices, which might raise some eyebrows with the news he's up to 325 pounds - eight more than his listed weight.
"My big deal is cutting out the ice cream, the Ben & Jerry's late at night - the stuff you want to indulge in," Johnson said. "If you get me on an ice cream binge, it's not good."
The Eagles can probably deal with a little extra ice cream, just as long as Johnson remains committed to keeping dodgy supplements out of his body.