AP Sports Writer
IRVING, Texas (AP) -- The top targets for an upgrade on offensive line were gone when the Dallas Cowboys' turn came in the NFL draft Thursday night.
So they traded down and settled for the next guy on their list.
The Cowboys took center Travis Frederick of Wisconsin with the 31st selection after trading down 13 spots in a deal with San Francisco, picking a versatile lineman that coach Jason Garrett thinks could also be a guard after playing that spot earlier in his college career.
The choice of Frederick came after the Cowboys missed out on the top two guards in the draft -- Jonathan Cooper of North Carolina and Chance Warmack of Alabama. Both went in the top 10.
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. Barring another trade, Dallas will have three picks in the second and third rounds Friday night.
"As always the incentive or the lure was to pick up a third-round pick and end up with still a first-round player that we thought would be as good as the one we got at 18," Cowboys owner and general manager Jerry Jones said. "That was our goal. And we think that's what we did."
The 6-foot-3, 312-pound Frederick started 31 of 32 career games at Wisconsin -- 13 at guard and 18 at center. He said he considered himself an early second-round pick, but spent a lot of time with the Cowboys before the draft.
Dallas took an offensive lineman in the first round for the second time in three drafts after going 30 years without taking a blocker in the opening round. Left tackle Tyron Smith was the ninth pick in 2011.
"They definitely need a little bit of help inside, and they were looking to upgrade that," Frederick said. "I think I'm going to fit in pretty well down there."
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 -- and Jones said later Dallas considers defensive line a position of strength even though the team is switching to the 4-3 defense and has a need for interior linemen. 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.
"Were there players that were graded ahead of Travis? Yes there were," executive vice president Stephen Jones said. "But I don't know that those players necessarily in our system were going to fit better for us when we look at our team over the next three, four, five years."
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.
Phil Costa entered last season as the starter at center but played just three games while battling ankle and back problems. He signed a two-year contract with nearly $1 million guaranteed in March, and Ryan Cook is signed through 2013 after starting 11 games following a trade with Miami late last preseason.
Garrett said the first priority with Frederick will be figuring out whether he plays guard or center.
"I think there's a lot to like about him," Garrett said. "He was the highest-rated player on our board when we took him at what we believe is a position of need."
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