Tony Romo is set to make his 2014 debut Saturday. So are other proven players, such as Dez Bryant, Jason Witten and DeMarco Murray.Those guys are known commodities. The Cowboys’ second preseason game against the Ravens is also about how the unknowns fare.Can linebacker Rolando McClain be an impact player? How will defensive tackle Ken Bishop do in place of Henry Melton? Is cornerback Sterling Moore the answer to Orlando Scandrick’s suspension?“It starts with individual evaluations,” coach Jason Garrett said. “You want to make sure you’re evaluating your team the right way, and we give everybody an opportunity to show what they can do, whatever their role may or may not be.”1Tony RomoHe’s expected to play in a game for the first time since undergoing back surgery Dec. 27. Owner Jerry Jones called Romo the “highlight of the camp,” a generous nod considering the star quarterback has been limited so far in camp. But all eyes will be on No. 9 and how he handles game action again.2The playmakersDez Bryant wasted no time in saying he’s ready to play in a game. Jason Witten and DeMarco Murray are ready, too, after sitting out the first preseason game. The Cowboys’ offense has a chance to be among the tops in the league, and it will need to be to offset the defense’s weaknesses.3Rolando McClainThe eighth overall pick in the 2010 draft has been praised by Cowboys officials, including Jones. But this is his first chance to show what he can do in a game, and the team is optimistic he can become a prominent player in the defense. If he does, it could help salvage what has the makings of being another defensive disaster.4SecondaryAs in the first preseason game, the secondary will be depleted. Cornerbacks Brandon Carr and Morris Claiborne won’t play, which should move Sterling Moore into a more prominent role. His reps are particularly important with Orlando Scandrick being suspended the first four games. And the team will also use the extra snaps to evaluate younger corners B.W. Webb, Terrance Mitchell and newly acquired Justin Green, who are competing for roster spots.5D-lineHenry Melton, a three-technique tackle whom the Cowboys are counting on this season, is sidelined with a groin injury. Melton is expected to be ready by the season opener, but the team is left experimenting with other linemen for the time being. Seventh-round pick Ken Bishop, widely considered a one-technique tackle, has shown promise early on and is expected to start in Melton’s place.
Drew Davison, 817-390-7760 Twitter: @drewdavison