PITTSBURGH -- On a defense that boasts a former Defensive Player of the Year, two Super Bowl rings and a combined 17 Pro Bowl selections, a former sixth-rounder on his fourth team might fly under the radar -- at least for those outside the UPMC Rooney Sports Complex.
Those inside, though, know safety DeShon Elliott is critical to the Pittsburgh Steelers' success.
And without an injury designation for Week 17 after missing two weeks with a hamstring issue, the safety's return is even more crucial as the Steelers face a multifaceted Kansas City Chiefs offense that boasts one of the league's best tight ends in Travis Kelce on Christmas Day (1 p.m. ET, Netflix).
"I wouldn't say he's under the radar, but hey, to each his own," cornerback Donte Jackson said of Elliott, shaking his head. "I would say one of the best doing it at his position right now, man. He's been phenomenal for us. And just from a communication standpoint, and the matchup standpoint, he's definitely been holding his own."
The numbers back that up. With Elliott on the field, the Steelers' defense is the best in the league. Without him, it's the worst. The Steelers allow just 4.8 yards per play, tied for best in the league with the Eagles, when Elliott is on the field. When he's not, that average soars to a league-worst 6.7. It's not just that Elliott is a fundamentally sound, effective tackler, it's that he plays with the hard-hitting attitude embodied by the ideal prototype of a Steelers defensive player.
"The biggest thing you miss with him is in terms of how physical he plays and the temperament he brings and the things he does in the run game," defensive coordinator Teryl Austin said. "Pretty exceptional. I think the guy's been having a great year. We know all about T.J. [Watt] and [Cameron] Heyward and those guys, but I think quietly this guy's been having an outstanding year, like really top-notch."
Elliott, who signed a two-year, $6 million deal with the Steelers in free agency, is a key part of the run defense. On Saturday, the Steelers gave up 162 rushing yards to Ravens running back Derrick Henry without him. Elliott ranks sixth in the league with 51 tackles on designed rushing plays, and he's second on the team with 96 total tackles. With an interception, 2 forced fumbles and 3 fumble recoveries, he has also been a key part of the Steelers' league-best 31 takeaways.
"He is really a physical, really in-the-box defender," Austin said. "Love the way he triggers in the run game and the physicality that he brings and the temperament that he brings. And you can see that you missed that a little bit with him not being in there. And so we're looking forward -- hopefully-- to get that back."
And though Elliott is known for setting the tone in run defense, the difference with him on and off the field in passing situations is even more stark. The Steelers are second in allowing 6.4 passing yards per attempt with Elliott on the field and last with 9.1 yards playing without him.
"We know he is a playmaker, a guy who communicates ... a physical presence and can cover as well," linebacker Patrick Queen said. "So it's definitely going to be nice if we have him back."
The timing of Elliott's return couldn't be any better. Elliott figures to be a key part of the Steelers' plan to defend Kelce. On the season, the Steelers have allowed 767 yards to tight ends, ranking 17th in the league. But the group ranks ninth with its average of just 6.6 yards per reception by the position. Elliott has been on the field for 89 of 117 snaps when opposing teams targeted their tight ends. With Elliott on the field, quarterbacks have completed just 66% of passes to their tight ends at 6 yards per attempt. That jumps to 89% (24 of 27) and 8.6 yards without him.
Though Kelce is averaging a career-low 8.3 yards per reception and has just two touchdowns, he leads the Chiefs in catches and the Steelers remain wary of the veteran big man and the array of weapons in Kansas City's offense.
"We'll probably have to do some different things," Austin said. "I don't think you can play this offense just one way and expect to survive. You have to be able to do different things. I think if you just line up and say, 'OK, hey, we're going to play a man all day,' they're going to eat you up. If you line up and just say you're going to play zone all day, they're going to eat you up.
"So we have to give a good mix in terms of coverage and disguise and the things that we do if we want to give ourselves a chance."
ESPN Research contributed to this article.