Chicago Bears kicker Robbie Gould has accepted responsibility for the franchise's overtime defeat to San Francisco 49ers on Sunday, admitting that he blew his chances to seal victory.

Two field goals from the 33-year-old had Chicago ahead 6-0 at the end of the first quarter, but he missed from 40 yards early in the second half and then crucially failed to convert a game-winning 36-yarder with the final play of regulation time before the Bears went on to concede a walk-off touchdown.

Gould called the two misses his worst kicks of the season, and admitted that any blame for the defeat should fall on his shoulders.

"I feel terrible," he told the Bears' website. "I have a job to do, and I did not do that today. I hit the ball really well in the first half, and I had a lot of confidence going into the last two kicks.

"I just got quick on both of them. I rushed them; I hurried them. Both are the worst kicks that I have had all year. This one falls on me and on my shoulders. I feel bad for my teammates because I did not do the job that I was supposed to do."

Gould, who joined the Bears in 2005 and is the franchise's all-time leading points scorer, entered week 13 of the season with an 86% success rate but he has now converted just nine of his 15 attempts since making his first 17 kicks of the campaign.