After watching their main targets get picked ahead of them, the Dallas Cowboys took center Travis Frederick of Wisconsin with the 31st selection in the NFL draft Thursday night after trading down 13 spots in a deal with San Francisco.
Offensive guards Jonathan Cooper of North Carolina and Chance Warmack of Alabama were taken in the top 10 and Texas safety Kenny Vaccaro went 15th to New Orleans -- three ahead of Dallas' original slot.
Dallas got an extra third-round pick in the deal with the 49ers, the 74th overall. The Cowboys have six picks for the remaining six rounds.
The 6-foot-3, 312-pound Frederick started 31 of 32 career games at Wisconsin -- 13 at guard and 18 at center.
The 60th draft-day trade since Jerry Jones bought the team in 1989 became more likely once Cooper and Warmack were gone, and the Cowboys were long shots to land either one.
With the guards off the board, a defensive choice was more likely from the 18th spot. When Missouri defensive tackle Sheldon Richardson went 13th to the New York Jets and Vaccaro was taken two picks later, the focus shifted to Florida defensive lineman Sharrif Floyd, who was projected as a top five pick by some.
The Cowboys decided they didn't want Floyd -- who went 23rd to Minnesota -- perhaps because he's a bit small for an interior defensive lineman at 6-foot-2 and 297 pounds. Dallas needs run stoppers more than pass rushers for the switch to the 4-3 defense. DeMarcus Ware and Anthony Spencer figure to be the starters at defensive end, and there are more questions in middle.
One other possible first-round target at defensive tackle -- Sylvester Williams of North Carolina -- went 28th to Denver, three picks before Dallas' choice.
In Frederick, the Cowboys have someone who could play either guard or center. He spent all of his senior year at center, where the Cowboys figured before the draft to go to training camp with Phil Costa as the starter.
Costa, who made just three starts last season while batting ankle and back injuries, signed a two-year contract in March. Ryan Cook is under contract in 2013 as well after starting 11 games following a trade with Miami late in the preseason last year.
The Cowboys targeted interior offensive linemen because they had the second-worst rushing offense in the NFL last season. They struggled despite adding guards Mackenzy Bernadeau and Nate Livings in free agency last year, although Bernadeau played center for several games because of injuries.
A run on offensive tackles in the first round -- five were taken in the first 19 picks -- left Dallas with the lingering question of what will happen to right tackle Doug Free, who had a rough year after moving from left tackle and ended up splitting time with undrafted free agent Jermey Parnell.