Look no further than the San Fransisco 49ers' two Pro Bowl representitives if you want a glimpse into their offense this season.

Tight end George Kittle emerged alongside stalwart fullback Kyle Juszczyk in a unit that's nothing if not one of the NFL's most unique; in a league that's primarily run out of three wide reciever, one back personnel sets, the 49ers instead opt for heavier, two back formations.

In fact, no one does it more often than San Fran. Per Sharp Stats, 41 percent of the 49ers offensive plays were run out of 21 personnel. That's far and away the highest of any team, with New England coming in 2nd at 28 percent. The rates continue to dramatically decline after that.

It starts with Kittle, who's played like one of the premier tight ends in football this season. Of all TEs, Kittle ranks 3rd in receptions (72), 3rd in receptions per game (5.14) and 2nd in yards per game (82.43).

Then there's Juszcyk, who so far has has 29 receptions for 309 yards and a touchdown. The fullback's on pace to have career-best years in total reception yards and yards per catch, too. Matt Nagy, who once coached Juszcyk in the Pro Bowl, knows the type of weapon he is.

"He’s difficult," Nagy said. "He’s a good player because he puts you, similar to like a 'U' tight end for us, where you can put him in the backfield and he’ll block a MIKE linebacker, and if you feel like that’s a disadvantage for them, they’ll move him out and go ahead and put him on a linebacker and run a route on them. He can do both of those really well. So you have somebody that can win in the pass game and win in the run game, that’s an advantage for them."

Fortunately for the Bears, an offense that runs through a pass-catching tight end matches up well with the likes of Roquan Smith and Danny Trevathan, both of whom are strong in pass coverage. The numbers back it up, too: according to Sharp Stats, the Bears are the 2nd-most succesful defense against tight ends in pass coverage. Opposing TEs are only averaging 5.8 yards per attempt against Chicago, which, would you look at that, is also second-best.

"Their offense does a great job of going to the run and then the play action," Trevathan said. "They're really big on that. We've got to be able to contain that like we have been all year. We've been one of the best in the league at the run game and being able to handle different formations. They open so many options with so many different formations and so many different shifts but we've been in this situation and we're prepared for and it."

It's easy to look at the 4-10 49ers and an offensive DVOA that ranks 27th out of 32 with skeptiscm. For the Bears -- who only rank 21st in success rate against RBs for what it's worth -- a Shanahan-schemed, two-back system with an elite pass-catching tight end provides plenty of challenges.

"They have a good variety of running game," defensive coordinator Vic Fangio said. "Any time you have two backs and the fullback can go anywhere to be a blocker, that does create more variety in the running game. They do a good job of that. They'll run the same plays every week, but they're running it out of different two-back looks, different actions, different motions. I think having the fullback and being committed to it and doing the good job they do with their playaction game off of it gives them good variety.

"It tests your eye discipline on defense and assignment and technique."

Even with having to line up against Kittle and Juszcyk, the NFL's best defense should be expected to handle a team that doesn't have their starting quarterback or starting running back and is missing one of their best wide receivers. For a division champion that's only 3-3 on the road, there's a whole lot to play for on Sunday.

The great teams find a way to win on the road and take that to the next step," Nagy said. "Our guys understand that. We’re going to have two road games here in a row that are going to be challenging. I don’t think there’s any magic to it."