ENGLEWOOD, Colo. (AP) Safety Shiloh Keo made a bad first impression when he joined Denver's dominant defense. He's more than made up for it with big plays that helped the Broncos reach the Super Bowl.
Five days after joining the league's top-ranked defense, Keo made a big blunder, surrendering the winning touchdown in the Broncos' stunning 15-12 loss to the Oakland Raiders.
Keo was a fifth-round pick in 2011 by Houston but hadn't played in the NFL since 2013. He had to lobby defensive coordinator Wade Phillips for a job on Twitter, and then was pressed into duty right after signing because an injury epidemic leveled the Broncos' depth at safety.
He helped them hold the Raiders to a paltry 126 yards in Week 14, including minus-12 yards in the first half. But after Emmanuel Sanders fumbled a punt deep in Denver territory, the nightmare unfolded for the street free agent who had been working out in hopes of signing a futures contract and making a comeback next season.
On third-and-15 from the 16, David Carr dropped back and threw to tight end Mychal Rivera, who whizzed past Keo and hauled in the game-winning touchdown pass.
Chided by his coaches, chewed out by his teammates and cursed by fans for not staying back in coverage, Keo vowed to make up for his mistake.
Has he ever.
Keo intercepted Philip Rivers with 5 minutes left in the regular season finale, setting up Ronnie Hillman's game-winning TD in Denver's 27-20 win that secured the AFC's top seed.
He topped that Sunday when he was pressed into crunch-time duty again along with Josh Bush when starting safeties T.J. Ward sprained an ankle and Darian Stewart sprained a knee.
Keo played 36 snaps on defense and 29 more on special teams.
He helped cover Rob Gronkowski on Tom Brady's 2-point conversion attempt, and when Aqib Talib tipped the throw to Julian Edelman into Bradley Roby's hands, they needed one more big play to seal the AFC title.
They got it from Keo.
He lined up right in front of kicker Steve Gostkowski, whose first missed PAT in 524 tries in the first half put them in this precarious position. The kicker had six teammates bunched to his right and four to his left.
He tried the straight-ahead on-side kick, but Keo sliced in and grabbed it 6 yards downfield, cradling both the football and redemption.
''What a gutsy play,'' coach Gary Kubiak said.
After he ran off in jubilation, Peyton Manning took a knee, sending the Broncos to their record-tying eighth Super Bowl, including a record seventh under owner Pat Bowlen, who's battling Alzheimer's.
Afterward, Keo sat in the corner locker, soaking in the moment with linebacker Brandon Marshall.
''When I think about it, I get emotional,'' Keo said, thanking both God and the Broncos.
''They believed in me, that's why they brought me here,'' Keo said. ''They trust everybody in this locker room. I just hope I can continue to come through and bring home a championship.''
Keo had a front-row seat to the epic beating Denver's front-seven put on Brady, who was hit an incredible 23 times.
''It makes `No Fly Zone' easy,'' Keo said. ''Quarterbacks have less time to throw.''
When he arrived in Denver, Keo spoke about how blessed he was to join one of the best defenses the NFL has ever seen.
He worried after his blunder against Oakland that he might have messed up Denver's mojo.
Kubiak and Phillips knew Keo from their time together in Houston, and they weren't about to give up on him so quickly.
''Obviously it's a coverage we should have handled better,'' Kubiak said the day after that loss to Oakland. ''We've got a couple of young guys back there playing who don't have a lot of snaps under their belt. ... We've got confidence in those guys. As we try to get David (Bruton Jr.) healthy and Omar (Bolden) healthy, those guys are going to have to play well for us.''
Bruton and Bolden both returned but got hurt again and landed on IR. When Stewart and Ward got hurt Sunday, Bush and Keo returned to the spotlight, combining for eight tackles and a pass breakup.
''Josh knocked a pass in the end zone and Shiloh had a clutch onside recovery where he looked like a shortstop,'' Ward said. ''So, I have a lot of respect for those guys coming off the street, learning the system and making plays whenever they're called upon.
''Guys go down and guys step up.''
And Keo went low to recover the on-side kick and make amends.
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