Cowboys to kick up Niners' prep work

IRVING, Texas -- The preparation for the San Francisco 49ers begins in earnest today, but the Dallas Cowboys have been looking at regular-season-opening opponent for some time now.

It started during training camp in Oxnard, California, and continued last week with two practices leading into the preseason finale against the Denver Broncos.

The 49ers have not lost a season opener under coach Jim Harbaugh, but they will be without three of their better defenders in linebacker Aldon Smith (suspension), linebacker NaVorro Bowman (injury) and defensive tackle Glenn Dorsey (injury). They could also be without defensive tackle Ray McDonald, who was arrested over the weekend on domestic violence charges.

“I know from our perspective (on offense), we’ve got a lot of respect for the way they play defense,” tight end Jason Witten said. “They’re a hit-you-in-the-mouth 3-4 team. Really good players across the board. It’s going to be a tough challenge. We’re going to see what we’re made of early in the year.”

And that’s why the Cowboys kicked off their prep work so early.