Mason Crosby's last-gasp 51-yard field goal steered the in-form Green Bay Packers into the NFC Championship game courtesy of a dramatic 34-31 victory over the Dallas Cowboys.

The Cowboys had rallied from 28-13 down to level matters following Dak Prescott's two touchdown throws, the second of which was followed by a two-point conversion.

Crosby and Dan Bailey then exchanged three-point kicks, the latter with 35 seconds left, but with overtime looming Aaron Rodgers' long pass found Jared Cook, whose toes were just inside the field of play when he caught the ball, to set up another field goal attempt.

Crosby nailed his first kick - although it was chalked off after Dallas coach Jason Garrett called timeout before the play - and held his nerve to split the posts again as time expired.

He was unsurprisingly mobbed by his team-mates after sealing the Packers' eighth win in a row which set up an NFC title decider against the Atlanta Falcons at the Georgia Dome next Sunday.

Meanwhile, the Pittsburgh Steelers booked their spot in the AFC Championship game after edging to an 18-16 win over the Kansas City Chiefs.

The Steelers are just another victory away from a ninth Super Bowl appearance although standing in their way will be Tom Brady's New England Patriots next weekend.

They were forced to hang on in the closing stages, though, as a one-yard touchdown from Spencer Ware closed the gap to two points. Kansas City went for the two-point conversion although their successful effort first time around was chalked off and their second attempt failed.