KANSAS CITY, Mo. -- The last time Derrick Johnson set foot in Arrowhead Stadium, he crumpled to the turf without anybody around him. As he stared up at the sky, his foot numb, the Chiefs' star linebacker had a sinking suspicion what was wrong.
"I didn't know for sure until later," he said.
Later, Johnson was diagnosed with a torn Achilles tendon, ending his season before he even reached halftime of the opener. He was just 15 tackles away from passing Art Still and Gary Spani and becoming the franchise's career tackles leader with an even 1,000.
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Nearly a full year later, Johnson is preparing to step back into Arrowhead Stadium. He made his return to games in the Chiefs' preseason opener at Arizona last weekend, but he acknowledged this week that playing at home Friday night against Seattle will feel a bit different.
"Being away from the game for a whole year, I've never done that before," he said. "Since I was 9 years old, I've always been in the football season."
The 32-year-old Johnson said he never considered retirement, even when he was lying on that turf so long ago. He was ready to confront the daunting challenge of rehab, even a year of it.
Still, none of the exercises in the weight room, or the miles he ran on the practice fields, or the massage and recovery and other rehab could get him ready for games. Johnson said the speed is different, and the way the game looks on the field is different from the sideline. Only by getting back in the action was he able to finish off his return.
"You got to train your eyes back," he said. "I'm training my eyes to make plays out there, as far as anticipating different things that I have to do. Football is a very hard sport. If you don't train your eyes, be spot-on with everything, you're going to be slow out there."
Johnson certainly doesn't look slow, ranging sideline to sideline to make plays throughout camp. Just about the only thing he's done wrong has been dropping an easy interception, but he quickly made amends when backup quarterback Chase Daniel threw him another one. Johnson not only caught it, but sprinted the other way for a touchdown.
It was the kind of athletic play that landed Johnson in the Pro Bowl three straight years, a streak that likely ended only because of his injury last season.
"D.J. is going to have an excellent year," Chiefs defensive tackle Mike DeVito said. "You just see him in practice and see him playing, and he's playing at such a high level."
Perhaps nobody can offer a better prediction than DeVito. He sustained a similar injury -- a torn Achilles tendon -- at almost the exact same spot on the field, just a handful of plays after Johnson went down. The silver lining to it was the two could rehab their injuries together, each pushing the other when things were at their most dire.
"We built a really strong bond," DeVito said.
The Chiefs missed both of them last season, but especially Johnson, who is so instrumental in stopping the run. Opponents routinely gouged the Kansas City defense on the ground the rest of the season, even though the Chiefs' pass defense was among the league's best.
"I felt last year, being out there without D.J., I kind of had to carry a load," fellow linebacker Josh Mauga said. "With him back this year, healthy and ready to go, it's nice how we both can carry the load together, and then use his experience being in the league for as long as he has been. I can feed off of him, feed off of his energy and pick his brain."
Indeed, one of the big benefits of having Johnson back on the field is his experience. The Chiefs have several young linebackers, including rookie Ramik Wilson, and Johnson has been able to help tutor them during the sweltering days of training camp.
But as much as he enjoys playing teacher, Johnson is a football player first and foremost. He belongs back on the field.
"For me being out for a year, preseason is very important to me," he said. "These preseason games are not as beneficial for older guys -- not as much. But for me, I need these games before the first game of the season."