Editing Super Bowl XII (section)

===Second quarter===
The Broncos were forced to punt to start the second quarter, and the Cowboys then advanced to the Denver 19 from their own 42, which featured a 19-yard pass by Staubach to DuPree. On third down, Staubach appeared to unleash a pass that was intercepted in the end zone by Broncos safety [[Bill Thompson (American football)|Bill Thompson]]; however, the officials ruled that Staubach had stepped out of bounds before he threw the ball. Herrera then kicked a 43-yard field goal to increase the Cowboys' lead to 13–0. The rest of the half was a seesaw of sloppy plays, turnovers, and missed opportunities. On the second play of the next Denver drive, Morton unleashed an errant pass intended for Moses for his third interception, this time by cornerback [[Benny Barnes]] at the Cowboys' 40-yard line. The Cowboys could not get points off of this turnover, as offensive tackle [[Ralph Neely]] was called for holding, which was followed by defensive tackle [[Rubin Carter (American football)|Rubin Carter]] sacking Staubach for a 5-yard loss, the fourth sack of the game for Denver, forcing a three-and-out and a punt. However, the punt struck an unsuspecting Schultz on his helmet as he attempted to throw a block during the return, and the ball was quickly recovered by Dallas linebacker [[Bruce Huther]].

The Cowboys then advanced to the Broncos' 26 on a 14-yard run by Dorsett, but Herrera missed a 43-yard field goal attempt wide left, keeping the score 13–0. On their following drive, the Broncos committed their fifth turnover as wide receiver [[Jack Dolbin]] fumbled a 13-yard reception, while being tackled by safety [[Charlie Waters]], with Hughes returning the ball 18 yards to the Denver 27-yard line. However, Dallas failed to score again as Herrera missed another field goal attempt wide right, this time from only 32 yards out. On the first play after that missed attempt, Denver yet again turned the ball over to Dallas when Kyle stripped the ball from tight end [[Riley Odoms]], with Hughes recovering it again and returning it to the 28-yard line. However, on the next play, Dallas gave the ball right back to Denver as DuPree caught a 20-yard pass at the 8-yard line but fumbled after taking a hit from cornerback [[Steve Foley (defensive back)|Steve Foley]], with Tom Jackson making the recovery. Five plays later, with the Broncos desperate to get on the board before the end of the half, Morton uncorked yet another errant pass that was intercepted by cornerback [[Mark Washington (cornerback)|Mark Washington]] who returned the ball 27 yards to Denver's 35-yard line. There were 6 seconds remaining on the clock after the interception, but Dallas yet again could not capitalize as Herrera missed yet another field goal attempt wide left, his third miss of the half, this time from 44 yards out, as time expired.
[[File:1986 Jeno's Pizza - 02 - Butch Johnson (Butch Johnson crop).jpg|thumb|left|Johnson's touchdown catch gave Dallas a 20–3 lead over Denver.]]
By halftime, the Cowboys had fumbled five times (losing one), had missed three field goals, and had allowed four sacks, but still led 13–0. Meanwhile, the Broncos had committed a halftime record 7 turnovers. Morton, who had thrown only 8 interceptions during the entire 1977 season, was picked off 4 times in the half in addition to 3 fumbles lost, finishing with a passer rating of 0.0. Incredibly, after punting on their very first drive of the game, six of the next seven Broncos possessions resulted in a turnover, and there also was a fumble on a punt return.