The Cowboys are the surprise of the early season. What’s behind it? Credit smart coaching, savvy personnel moves and a host of unheralded players stepping up

The Cowboys, tied for the league lead at 4-1, are for real, and not many saw this coming. Probably not even themselves, if they told you the truth before the season started. The offense was going to be good (it’s been better than expected because of an outstanding offensive line), but you didn’t know how Dallas was going to line up, let alone function, on defense.

Franchise pass rusher DeMarcus Ware was released in the offseason. Second-round pick DeMarcus Lawrence, Ware’s replacement, broke his right foot in July and can’t play until Week 9. Defensive tackle Henry Melton, who was signed to replace Jason Hatcher after the latter signed with Washington, missed the entire preseason with injuries. Terrell McClain, another free agent tackle, has played only 75 snaps through five games. Inside linebacker Sean Lee, one of the league’s top defenders when healthy, was lost for the season in May and replaced by a player in Rolando McClain who was out of football in 2013 and dealing with a variety of off-field issues.

Defensive coordinator Rod Marinelli called the situation “challenging” just before the opener against the 49ers. Coach Jason Garrett assessed the team’s personnel in coachspeak. “We have a lot of different combinations of guys that have come from a lot of different places,” he said. “We like the competition. We think that’s good, and we think everybody is benefiting from it.”

Rolando McClain, who was out of football last year, has shown the kind of form that made him a top-10 draft pick. (Greg Nelson/SI/The MMQB)

Translation: Yeah, we don’t know what the hell we’re going to do either.

It hasn’t always been pretty, this 4-1 start. The Cowboys are giving up 6.49 yards per play, last in the league. But they’ve figured out a way to keep the opponent out of the end zone—they’re 10th in points allowed, at 21.5 per game, and have held the Saints and Texans to 17 points each in the past two games.

While there’s a feeling that the Cowboys’ defense has been playing on borrowed time and that giving up so many yards will catch up with them (perhaps this week on the road in Seattle), the unit looks transformed under Marinelli after bottoming out a season ago under Monte Kiffin, Marinelli’s mentor.

Yes, Marinelli is an aggressive coordinator and is not afraid to bring pressure, especially from the secondary, but the secret to the Cowboys’ defensive resurgence seems to have been simply a return to the basics—they tackle very well—and a more physical persona.

And there have been key contributions. End/tackle Tyrone Crawford, a third-round pick in 2012 who didn’t start before this season, has been revelation both against the run and rushing the passer. He’s shown a knack for playing inside when he’s gotten the opportunity. With Melton playing at a high level, the Cowboys have two tough matchups on the defensive line.

Linehan has long been one of the best-play-callers and game-planners in the league. He’s deftly mixing the play-calling to keep defenses off balance.

McClain, despite battling a groin injury, has shown the type of instincts and physical ability that made him the eighth overall pick by the Raiders in 2010.

The passing defense has been much more competent since Orlando Scandrick returned from a two-game suspension. He’s been one of the better slot corners in the NFL for some time, and he finally got a chance to show he could be a starting cornerback last season. And Sterling Moore has continued to be a solid if unspectacular role player, as he was for the Patriots in 2011 and ’12.

The home-grown line is giving Romo the kind of protection he isn’t used to. (Greg Nelson/SI/The MMQB)

Offensively, everything starts with the line. The unit of LT Tyron Smith, LG Ronald Leary, C Travis Frederick, RG Zack Martin and RT Doug Free is outstanding. They are the reason why DeMarco Murray leads the league in rushing. He’s a good player with a nice burst to get to the second level and is tough to bring down, but the line is the key to the Cowboys’ success. And it’s all home-grown. Smith, Frederick and Martin are first-round picks. Free was a fourth-rounder, and Leary was an undrafted free agent in 2012. Putting that line together is a reason why people shouldn’t scoff when owner Jerry Jones is mentioned as a candidate for executive of the year.

When Garrett selected Scott Linehan as offensive coordinator to replace Bill Callahan, who was demoted, it looked like another coaching blunder for the Cowboys. But Garrett has clearly gotten out of the way and allowed Linehan to run the show offensively. That was a wise decision. Linehan has long been one of the best play-callers and game-planners in the league. He’s keeping the Cowboys balanced and is deftly mixing the play-calling to keep defenses off balance.

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The Cowboys show signs of still being the circus Cowboys. There was the unconscionable delay of game penalty against the Texans with 2:23 left in the fourth quarter—after a timeout—that helped give the Texans the ball back and score the tying touchdown. Romo also has to realize that his days of playing behind an underperforming offensive line are over. He can’t hold onto the ball forever to make a play like he used to. To his credit, Romo is dumping the ball off to the outlet receiver or running back much more often. He needs to be more consistent with that. The Cowboys only need Romo to be a smart game manager with sound mechanics (he loves to revert to throwing off his back foot and falling away) to direct this offense to new heights.

Dallas’s defense has been a huge revelation to this point, but that may not last. To continue winning, the offense must to continue to be efficient and take care of the ball better. The Cowboys have surprised everyone to this point, probably even themselves. Now the question is, can they live up to the new, higher expectations they’ve created?

GALLERY: ROMO’S GREAT ESCAPE

It’s not often that any quarterback eludes the grasp of Houston’s J.J. Watt, but Tony Romo did just that—to the shock of Watt, not to mention most observers—in the third quarter, spinning out of Watt’s grasp and then heaving a 43-yard touchdown pass to Terrance Williams to give Dallas a 10-7 lead. Photographer Greg Nelson caught the action.