Safety Kenny Vaccaro had an impressive day. He didn't run the 40 because of a hip flexor injury, but he displayed a burst, lateral movement and quickness while performing position drills for Cincinnati Bengals defensive coordinator Mike Zimmer. Vaccaro said he's studied various defenses, including the Tampa 2, and is getting ready for the NFL game from a mental standpoint. Vaccaro said he was disappointed he couldn't run the 40, but indicated that he has run it in the low 4.40s during training. Vaccaro injured the hip while working out but re-injured it during his drill session with the Cowboys last week. After three drills, Vaccaro shut it down so he wouldn't further injure himself. Vacarro said his goal is to be the first safety taken in the draft.

Defensive end Alex Okafor needed a solid pro day to prove to NFL scouts that he's healthy and worthy of a Day 2 draft selection. He declined the bench press, standing on his combine numbers of 21 times at 225 pounds, but he ran a 4.88 and a 4.96 in the 40 and was concerned about being too stiff when he worked on his individual drills. Okafor ran through some of the drills smoothly and looked comfortable, but he still needs some work. Okafor said he believes he can play defensive end in a 4-3 or outside linebacker in a 3-4. Weight could be an issue. He came in at 262 pounds and might have to pick up more bulk to play end.

Vince Young looked slim and seemed to be in good spirits during his pro day. Most, if not all, of his throws were tight spirals and he displayed good arm strength. It seemed that when he threw to a variety of receivers inside and outside, he didn't have that funky shot-put motion. Young is throwing more traditionally and no longer appears to be dropping his elbow low when he throws.

Running back D.J. Moore ran the fastest 40 time of the prospective draft picks in 4.41 and 4.38. One negative: Size. He's listed at 5-foot-9, but he measured at 5-foot-7, 175 pounds. That's not to say little guys can't play in the NFL, but it will be hard for him to get significant playing time at running back unless he impresses an NFL team during training camp. He might be a solid return guy on the next level.

Wide receiver Marquise Goodwin measured in at 5-foot-9, 177 pounds -- good size for a slot receiver. He didn't run the 40, however his three tries at the vertical jump were 41, 42 and 42 inches. Goodwin has the speed it seems to make some plays from the slot at the next level. He just needs to make sure he can be a consistent player.

Pittsburgh Steelers coach Mike Tomlin attended the pro day. The Cowboys had two scouts, and Denver, Cincinnati, Indianapolis, Houston, Miami, Kansas City, Oakland, Cleveland, the New York Jets and San Diego also had reps in attendance. ... Texas coach Mack Brown and former running back Ricky Williams were in attendance. ... Most scouts will either go to LSU's pro day Wednesday or SMU's.