Under pressure

After Dallas Coach Bill Parcells made Tony Romo the starting quarterback over veteran Drew Bledsoe at midseason, the Cowboys won five of their next six games.

So, in a matter of weeks, Romo went from an unknown four-season backup to the second coming of Roger Staubach and Troy Aikman as Dallas charged to the top of the NFC East standings.

Romo passed for 10 touchdowns with only four interceptions as he excelled managing Parcells’ run-based offense. Although Romo did a great job of getting the ball to tight end Jason Witten and keeping Terrell Owens happy, the coach praised him most for not making unforced errors.

But Romo and the Cowboys’ honeymoon ended once opposing defenses started to figure him out, beginning with New Orleans on Dec. 10.

The Saints followed the textbook plan on how to rattle a young quarterback, frustrating Romo with a scheme of blitzes that pressured him all game. New Orleans sacked Romo twice and forced him into bad throws with a variety of complex coverages. The Saints won, 42-17, with Romo completing 16 of 33 passes for 249 yards and a touchdown with two interceptions.

Because the NFL is a copycat league, every opponent since has followed New Orleans’ game plan and Romo has been unable to figure things out quickly.

Even lowly Detroit, which fired its defensive coordinator this week, made Romo look ordinary. Although he passed for 321 yards and two touchdowns, Romo didn’t make enough plays in the Lions’ 39-31 victory on the Cowboys’ home field.

Romo’s safety net continues to be Witten, who has caught at least three passes in every game since Bledsoe was replaced. But Romo has had trouble completing deep throws to Owens, who has attracted double coverage all over the field.

That’s part of the reason why, after completing better than 65% of his passes in his first five starts, Romo connected less than 50% of the time in two of his last four starts.

In order for the Cowboys to pick up a victory at Seattle on Saturday, Romo must find a way to dissect pressure defenses that use interchangeable defenders. He can do that with quick, short passes early in the game to help Dallas get into an offensive rhythm. What he can’t afford is to hold onto the ball too long against the Seahawks’ blitzes.

Romo has to be in position to take advantage of man coverage against wide receivers Terry Glenn and Owens. If Seattle concentrates on stopping the run, Romo needs the freedom to audible to plays to get the ball to his playmakers.

The Cowboys can also help Romo with effective running by Julius Jones and Marion Barber. Jones, who led the team with 1,084 rushing yards, is expected to give up carries to Barber, who has emerged as a power back.

Another key for Romo, who had eight interceptions and only six touchdown passes in December, will be for the Cowboys not to fall behind early.

When he led Dallas on its midseason rise, Romo mostly played with a lead and was able to find open receivers on play-action plays.

But since the Cowboys defeated the New York Giants on Dec. 3, their defense has been awful, giving up 33 points a game over the final four weeks of the regular season. And in three of their last four games, the Cowboys have trailed by double digits in the first half.

Romo is going to need every break he can get against the Seahawks, who are 5-3 at home. The more help Romo can get from his teammates, the better the chance the Cowboys will regain their midseason form.

lonnie.white@latimes.com

*

Matchups for wild-card weekend

Kansas City at Indianapolis

Saturday, 1:30 p.m., Channel 4

----

Dallas at Seattle

Saturday, 5 p.m., Channel 4

---

New York Jets at New England

Sunday, 10 a.m., Channel 2

---

New York Giants at Philadelphia

Sunday, 1:30 p.m., Channel 11