Both Jay Cutler and Colin Kaepernick entered the 2014 season with massive, $100 million contract extensions to live up to. So far only the San Francisco 49ers star has proven worth the investment.

Kaepernick lit up the Dallas for a 201 passing yards and two touchdowns in San Francisco’s 28-17 Week 1 victory, while Cutler’s 349 yards and two touchdowns were marred by two costly interceptions in the Chicago Bears 23-20 overtime home loss to Buffalo.

While the 49ers look to keep pace with Seattle in the NFC West, the Bears risk falling behind two games in the very tough NFC North as they head to Levi’s Stadium Sunday night.

Cutler’s propensity for turnovers has long plagued him since his days with Denver, but his gunslinger ways could put Chicago down early if the 49ers defense played like it did against the Cowboys. All told San Francisco, which lost key contributors like safety Donte Whitner and cornerbacks Carlos Rogers and Tarell Brown to free agency and won’t have defensive lineman Aldon Smith until the second half of the season due to suspension, forced four Dallas turnovers and sacked quarterback Tony Romo three times. The Cowboys didn’t even reach the end zone until late in the third quarter

Chicago’s offense hummed from the start against Buffalo, with Cutler going 3-for-3 on the opening drive, capped by a 12-yard touchdown pass to tight end Martellus Bennett in the first quarter. But on their next four drives the Bears would punt twice, Cutler would throw his first interception and receiver Brandon Marshall coughed up a fumble to fall behind 17-7 heading into halftime.

Marshall redeemed himself with an 11-yard touchdown grab to tie the game 17 all, but in the fourth quarter committed and was penalized for a horse collar tackle on Buffalo’s Kyle Williams, who hauled in Cutler’s second interception on the day.

It was also a messy affair for the Bears defense, which gave up 193 yards on the ground, and struggled to rush Bills quarterback E.J. Manuel, sacking him once and only hitting him another three times.

There could be a couple of injury questions for the Bears. Marshall injured his ankle in the third quarter, and though he insisted to the Chicago Tribune that he will play, it’s possible he won’t be 100 percent against the 49ers. No. 2 receiver Alshon Jeffery also came up with a hamstring injury in the third quarter, and was set to return but the Bears exercised caution. Up to that point Jeffery had totaled five catches for 71 yards.

Center Roberto Garza and left guard Matt Slauson also suffered ankle injuries. NBC Chicago reports the Bears signed Eben Britton to create some depth to the bang-up o-line, and that if Slauson can’t play Michael Ola would likely start and Brian de la Puente would step in for Garza.

But it’s not as if the 49ers are 100 percent healthy either. Defensive back Chris Culliver left the Dallas game with a concussion, and rookie safety Jimmie Ward also left late in the fourth quarter after a big hit. However according to the Sacramento Bee, Ward wasn’t diagnosed with a concussion and won’t have to pass the NFL’s post-concussion protocol. Cornerback Tramaine Brock also suffered a sprained toe early against Dallas and is listed as day-to-day.

Prediction: Chicago’s inability to prevent the run could mean a big day for 49ers running back Frank Gore, and for Kaepernick if he decides to take off. The Bears could have put a stranglehold on the Bills if it weren’t for their turnovers, and if Cutler can keep things under control (and Matt Forte can be effective out of the backfield), Chicago can pull off a big victory. San Franciso’s secondary is a little banged up, but not enough to slip up too badly at home.

Betting Odds: San Francisco -7

Over/Under: 48.5 points

Predicted Score: San Francisco 27, Chicago 17