KANSAS CITY, Mo. (AP) Derrick Johnson knew his season was over the moment he hit the frozen turf of Arrowhead Stadium, the Chiefs' veteran linebacker ripping off his helmet in frustration.
It became official when he went to the sideline and found he had torn his Achilles.
The injury only briefly deflated Kansas City on Thursday night, though. The Chiefs' defense seemed to rally around their fallen leader in the second half, shutting down the Oakland Raiders to preserve a 21-13 victory that gave them control of the AFC West.
''He's a guy I respect so much, and just to see the look on his face when it happened, it looked serious,'' Chiefs quarterback Alex Smith said. ''There's not a guy in the locker room that doesn't look up to D.J., so yeah, in a big game like that, hat's off to our defense for responding.
''Something like that can hurt you big-time and our guys didn't miss a beat.''
Kansas City had just taken a 21-3 lead in their AFC West showdown when Johnson fell to the turf away from the play. The look of frustration on his face was evident as the training staff and coach Andy Reid ran onto the field, and as his left shoe was removed and the examinations began.
Johnson was helped off the field without putting any weight on his foot, and he spent the rest of the half sitting on one the heated benches in somber silence.
''I felt a little bit of a letdown when it happened, but Justin (Houston) and Eric (Berry) reeled everyone in and got after it. The last thing D.J. would want is a letdown.''
Johnson ruptured his right Achilles in similar fashion two years ago, and the Chiefs proceeded to lose the game. But this time, they managed to squeak out a crucial win for their playoff hopes.
''We made adjustments but we got it done,'' fellow linebacker Dee Ford said. ''My heart goes out to him. It's hard. But we're going to keep moving. That's life. But we're going to miss him.''
The 34-year-old Johnson, already the Chiefs' career tackles leader, had been having another stellar season. He came into the game with 89 tackles, a sack and an interception that he returned for a score to highlight the first year of a $21 million, three-year deal that he signed in March.
Kansas City was already without middle linebacker Josh Mauga, who had season-ending surgery to his hip in training camp, and Justin March-Lillard, who had surgery on a broken hand in October.
Reid indicated it's possible that one of them could return before the playoffs.
''That's part of the equation,'' Reid said. ''We'll discuss that tomorrow, but that's part of the equation. We have the flexibility to do that.''
The Chiefs also lost defensive tackle Rakeem Nunez-Roches to back spasms in the first half, while Oakland was missing three starters at kickoff after offensive lineman Kelechi Osemele was scratched with an illness that ultimately landed him in the hospital.
Safety Karl Joseph had already been ruled out with a toe injury and defensive tackle Stacy McGee was out with an ankle injury.
''I saw him prior to the game and there was no way I could ask him to try,'' Del Rio said of Osemele, who has also been dealing with a knee injury. ''Not trying to get into specifics, (but) it was significant enough we wanted to make sure we got him to the proper care.''
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