If the Cowboys had played like a team without a lead on Sunday night, that would have been understandable.

They lost edge rushers Dorance Armstrong and Dante Fowler Jr. to Dan Quinn and Washington in the spring; lost Sam Williams for the season in Oxnard, California; lost Micah Parsons and DeMarcus Lawrence for the time being in a battle to beat the Giants last week; and lost rookie second-round pick Marshawn Kneeland in the first quarter against Pittsburgh.

It’s hard to take six edge rushers from a team in that time and not see major consequences. Still, the Cowboys defense came up with more sacks than Pittsburgh, even though Dallas was much more pass-prone than the Steelers on Sunday night. Yes, in the final seconds, Dak Prescott became the hero by hitting Jalen Tolbert for the game-winning touchdown with 20 seconds left in a 20-17 win in Dallas. But the defense kept the Cowboys alive through the first three quarters as Prescott had huge problems with two interceptions – one a very poorly thrown ball at the goal line – and lost a fumble on another scoring opportunity.

The Cowboys defense prevented Pittsburgh from gaining any significant momentum from these miscues. A team without Parsons and Lawrence up front, without Daron Bland and rookie Caelen Carson at corner made enough plays to shut down the Steelers’ running game and hold the home team to 17 points for the win.

It was only natural that the NBC Football night in America crew hyped the fact that the Steelers and Cowboys are the only teams to ever meet in three Super Bowls. Just seeing the two iconic uniforms in prime time is enough to bring back memories for fans of both sides – memories for those of us who have been around a while. Indeed, Dallas and Pittsburgh played in three Super Bowls. They came during the Ford, Carter and first Clinton administrations.

This was not a super performance from either team, each of whom had more hope of being labeled as playoff candidates this season than Super Bowl candidates. Some uneven moments may have been forgivable after both waited through a lightning delay of 1 hour and 23 minutes, meaning the fourth quarter didn’t start until after midnight Eastern time.

Although Pittsburgh expected to start this season with Russell Wilson at quarterback, his calf injury has sidelined him for the first five weeks, leaving former Bears first-round pick Justin Fields in charge. While no one will mistake Fields, an excellent runner, as one of the game’s best passers, he had been efficient enough through the first four weeks to at least post a 90 passer rating in all three of the Steelers’ wins and the loss of the club against the Colts last. week.

Fields managed two touchdown throws to keep the passer rating streak alive, but efficiency really wasn’t his calling card Sunday night. Dallas’ defense forced five punts and heavily covered senior receiver George Pickens. Fields had to spread the ball around to other wideouts and tight ends as Pickens was limited to two catches for 29 yards until he made a short grab on the final lateral-filled play that amounted to nothing more than a fumble recovery for the Dallas defense .

Fields’ final numbers were 15 for 27 for 131 yards. That’s 221 fewer yards than Prescott produced against a much healthier defense and one that had certainly been more successful in the first month of the season than the Cowboys’ unit.

Because Rico Dowdle saved Dak at times by keeping drives alive and making the reception on one of two Prescott TD passes, the Cowboys actually beat Pittsburgh on the ground, something no one likely would have predicted based on recent results. The Cowboys defense held Najee Harris to 42 yards and a 3.0 average and limited the elusive Fields to 27 yards on six carries.

We know the competition the Cowboys will face in the coming weeks will be tougher on the offensive side. That starts on Sunday with Detroit at AT&T Stadium and certainly also applies to the 49ers, even though San Francisco currently (awkwardly) has a worse record than the Cowboys. Atlanta, Houston, Washington, Philly – all these offenses are coming up in November, when the Cowboys will presumably have Parsons back. Lawrence’s return could happen somewhere along that stretch.

Meanwhile, the Cowboys got three sacks Sunday night from the unlikely group of tackles Linval Joseph, ends Chauncey Golston and Tyrus Wheat and tackles Osa Odighizuwa and Carl Lawson (half a sack each). It’s a makeshift group that Mike Zimmer has managed to glue together to secure back-to-back road wins.

Suddenly, the Cowboys’ once-powerful offense can only put up 20 points per game. Suddenly — in the Cowboys’ defense against New York and Pittsburgh — that’s enough to get the Cowboys back above the .500 mark and start thinking about how to make the road ahead less intimidating.

Photos: Cowboys rally for comeback win in rainy Pittsburgh

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More on the Cowboys win over Pittsburgh

– Five lessons from Cowboys-Steelers: Dak Prescott leads Dallas to dramatic victory

– Persistent Dak Prescott survives costly mistakes to lead Cowboys to victory in Pittsburgh

– Dak was the hero, but the Cowboy defense deserves all the credit in the dramatic win over the Steelers

– Tim Cowlishaw’s Cowboys-Steelers report: Don’t minimize the importance of this win

– National reaction to Cowboys-Steelers: Dallas plays late-night thriller in Pittsburgh