Here are 10 things worth keeping an eye on in Sunday’s Patriots-Bears game:

WHEN THE PATRIOTS HAVE THE BALL

Running the football. Sunday will mark the third time in the last five games the Patriots will face one of the three best running defenses in football. And after beating Pittsburgh (first with just 62.3 yards per game) and New York (third and 87.5 yards per game), they get their crack at Chicago (second in the league at 84.9 yards per game.) In the wins over the Steelers and Jets, the Patriots made sure to maintain a healthy balance of run and pass, getting up in the second half of both games and using a combination of BenJarvus Green-Ellis and Danny Woodhead to help keep the clock and the chains moving in the third and fourth quarter. Much of what we’ve seen — at least at the start of those games — has been the Patriots tendency to start with either four or five wide in an attempt to spread the field and create some favorable offensive matchups, using the pass to set up the run. That could open things up in the running game for New England, especially on an afternoon that's supposed to be cold and snowy.

Keeping the Chicago defensive ends at bay. The combination of Julius Peppers and Israel Idonije — the two defensive ends in the Bears’ 4-3 defensive front — are tied for the team lead in sacks with seven each. Peppers is just the kind of sizable speed rusher who gives Matt Light fits coming off the end, while right tackle Sebastian Vollmer has taken a step back after a sensational rookie year. The two will likely get plenty of help in the form of tight ends Alge Crumpler and Rob Gronkowski, who will likely stay in to block to offer at least a chip on the ends before the start their patterns.

“He's a great athlete, to start with. He plays hard. He's always going and he's not stopping. You respect guys who play hard and are trying hard,” Patriots offensive lineman Logan Mankins said of Peppers. “I don't know what we could really say about Chicago, other than they're good all the way around. Their defense is really good. They've got a good front four and good linebackers, so it's going to be a tough day on Sunday.”

Protecting the football. The Patriots are uncommonly good at protecting the football, both when it comes to avoiding fumbles and interceptions. Quarterback Tom Brady has thrown a pick since October 17, and on Monday, he extended his streak to 228 consecutive pass attempts without an interception, a team record. In all, he has now gone seven straight starts without an interception, setting a franchise record for most consecutive starts without an interception.

However, like the Patriots, the Bears have had success this season when it comes to interceptions — Chicago’s 16 picks are tied for third in the NFC. D.J. Moore has four interceptions, while Charles Tillman and Chris Harris have three each. Moore, who has worked fairly exclusively at nickel corner, has become a bit of a breakout star in Chicago, turning into a playmaker on the field and a great quote off the field — he told Chicago reporters this week that the thing he respected most about Brady was “his taste in women.”

“D.J. has great instincts and as good a hands as anybody on our team,” Chicago coach Lovie Smith told reporters this week. “And the nickel position has an opportunity to make a lot of plays. When you have the right guy there, you can make a lot of plays.”

Creating mismatches in the passing game. Brady and the New England offense were able to exploit several mismatches last week and came away with big gains against the Jets, including one play where Wes Welker was lined up against linebacker Bart Scott and Danny Woodhead was one-on-one with defensive tackle Mike DeVito. The Bears have some more defensive versatility when it comes to facing the pass — linebacker Brian Urlacher plays more like a safety — but the Patriots will still try and create the same sort of mismatches using Welker, Woodhead and Deion Branch, as well as rookie tight ends Rob Gronkowski and Aaron Hernandez. One thing that is important to remember is that the Bears are a 4-3 team that predominantly employs a Tampa-2 scheme, and Brady has traditionally done very well against teams that use the Tampa-2 like Indianapolis and Jacksonville.

WHEN THE BEARS HAVE THE BALL

Pressuring the pocket. The Chicago offensive line has had major issues in pass protection all season long, yielding a league-high 45 sacks. Expect the Patriots to shuffle their front a little bit in hopes of taking advantage of some potential mismatches, especially the right side where the Bears start two rookies — J’Marcus Webb at right tackle and Edwin Williams at right guard. (The move of Wilfork off the nose to end in New England’s 3-4 set would seem to be a natural decision here.) And while it seems unlikely, New England could get a big boost by the possible return of Mike Wright, who has been sidelined now for almost two weeks with a concussion. Wright, who leads the team in sacks with 5.5, is the Patriots best pass rusher among their interior linemen, and could also be used to exploit some potential mismatches up front.

Picks are primary. New England has few peers when it comes to forcing turnovers — the Patriots have 18 interceptions on the season, and are plus-14 when it comes to takeaways. Rookie corner Devin McCourty leads the way with six picks, while veteran safety James Sanders has three. (Both picked off Jets quarterback Mark Sanchez once on Monday night.) In addition, linebacker Rob Ninkovich, safety Brandon Meriweather and safety Patrick Chung have two each. While Cutler isn’t the interception machine he was last season (he had 26 last year, but he has just 10 this season), he’s still prone to occasional wildness —he had a season-high four in an October loss to the Redskins. The bottom line is that if New England comes away with at least one interception, it’s probably going to win the game — in their 10 wins, the Patriots are plus-19 in the turnover battle; in their two losses, they are minus-5.

Stopping Matt Forte. The running back is consistently Chicago’s No. 1 offensive option, and has accounted for 748 rushing yards and 389 receiving yards — only one of 10 players in the NFL this season who has passed both plateaus. (He leads the team in rushing touchdowns with five.) While Devin Hester remains a threat to break out at any time, Forte is a more consistent offensive presence for the Bears, and has broken more than his share of big plays for Chicago this season. Forte has 18 runs of 10 yards or more and five of 20-plus. In fact, in many ways, he has been utilized in the same fashion as Mike Martz used Marshall Faulk while Martz was in St. Louis.

“[Matt] Forte has been tremendous with big plays, running, passing,” said Patriots coach Bill Belichick. “You don't often see big plays made by players at that position as often as he makes them in both the running game and the passing game. He's extremely dangerous.”

Containing Greg Olsen, especially in the red zone. The 6-foot-5, 255-pound tight end out of Miami is second on the team in receptions with 56 (he’s got 336 receiving yards), but is leaned on primarily as a red-zone threat — he’s got five touchdowns on the season. The Patriots did a very good job containing the Jets’ Dustin Keller last week (holding him to three catches for 27 yards) with a series of coverages. That should be more of the same this week, as a variety of safeties — Sanders, Meriweather and Chung — should work as a group to try and slow down Olsen. (For what it’s worth, Olsen is a big reason why the Bears are one of the better teams the Patriots have faced in recent weeks when it comes to converting touchdowns in the red zone. Chicago has had 38 red-zone touchdown chances, and has reached the end zone 19 times, good for a 50 percent rate.)

“[He’s] a vertical threat, with good speed. He’s good receiving tight end. We're going to have our hands full with him. He's a great player,” Sanders said of Olsen. “We get a lot of good work in practice. We have some of the best tight ends in the league, I feel, and we see them each and every day. They prepare us as much as possible leading into the game. They are similar — they're real athletic guys. [But Olsen is] a big guy who runs well, so we're going to have to have our ‘A’ game in Sunday to control them.”

SPECIAL TEAMS

This is an area where the Bears would appear to have a decided advantage for several reasons. Devin Hester remains the most electric return man in the league — he’s returned two punts for touchdowns this season — and kicker Robbie Gould (a former training camp invitee of the Patriots in 2005) has become one of the best and most reliable young kickers in the league, particularly as he deals with the windy conditions at Soldier Field. While both kickers will be dealing with a new field surface, Gould is far more experienced than New England kicker Shayne Graham when it comes to kicking in the Soldier Field elements. Despite the fact that he’s been pretty dependable in his brief career with the Patriots when it comes to field goals and extra points, the fact that it’s supposed to be cold and snowy on Sunday afternoon probably won’t help Graham.

For a kicker, working on a new surface has some challenges.

“It’s just like every time you walk out on the practice field — you never know how worn out and torn up it’s going to be,” Graham said. “When you have a new surface, both teams have to play on the same field, so you take the time you have before the game to take the right cleats out, to see what gives you the best footing and what type of things you need to do to soften your adjustments or anything to trying to be a little easier on us so you’re not putting so much pressure on your cleats when you’re trying to plant and everything. But you try and adapt to it the best you can. Sometimes it can be really bad, but I’m sure they’ve taken care of it and I’m sure it’ll be in the best possible shape it can be in.”

INTANGIBLES

With the exception of a 10-penalty performance against the Steelers last month, the Patriots have managed to steer clear of impactful penalties over their most recent stretch. Despite the fact that there has been a lot of pushing and shoving after the whistle late in the most recent stretch of the games, New England has cut way down on penalties as of late, a run that culminated in being flagged for just one penalty last Monday against the Jets, tying a season-low. Overall, New England has been whistled for a total of seven flags over the last three games, and they have 61 on the season, third-best in the league behind the Falcons (48) and the Dolphins (50). Another flag-free afternoon for the Patriots Sunday against the Bears would go a long way toward winning the ballgame and clinching that playoff spot.