LAKE FOREST, Ill. (AP) - Chicago Bears' defense is finding it difficult to close out games and showing signs of some real wear and tear.

Playing without injured linebacker Brian Urlacher and with several other lineup changes, the Bears will have to find a way to turn it around Sunday against a Minnesota Vikings offense that can run opponents into the ground behind Adrian Peterson. A win would also help erase the sting of the 23-17 overtime loss to Seattle at Soldier Field last weekend.

The Bears defense has failed on three of the last four attempts when handed an opportunity to close out a game. With five 30-something players, the conditioning and stamina of the defense has been closely watched. They allowed Seattle to convert eight of 15 third downs, a season's worst 53 percent.