Let's look at some key defensive players that will be watched closely on Saturday night in San Francisco.
DE Joe Jackson: If you watched the Blue-White Scrimmage in person or online, that might've been your introduction to the Cowboys' rookie defensive end. He chased down fellow rookie Mike Weber across the field for a tackle in team drills, prompting this praise from Cowboys owner Jerry Jones: "This is his first time we've had the live action and I'm telling you he was really impressive. He was all over the field." Jackson has continued to be active as a rusher in practice the past week. The Cowboys were pretty surprised in April when the former Miami (Fla.) standout was still on the board in the fourth round. He's a powerful defensive end at 285 pounds and he might be able to help the line inside as a rusher in certain situations.
Donovan Olumba: To this point, Olumba has had a really successful camp. He continues to make plays and show up in practice, and he's standing out among a crowded cornerback depth chart. The problem is obviously that he's a low man on the totem pole. This position is loaded, so it might be difficult for Olumba to make the roster — even if he has an outstanding camp. One way to change his fortunes could be to ball out in the games. If he's capable of continuing his development on the big stage, he could make himself impossible to ignore when the coaching staff trims down this defense. The first hurdle for him is Friday in Santa Clara.
Jalen Jelks: There's really no one else that I could pick right now. I've been singing his praises since he was drafted. I just have a good feeling about what he will bring to the team, and nothing that has occurred here at camp has changed my opinions right now. Jelks has been good in practice – with the occasional big play, either in team drills or 1-on-1. Let's see how he stacks up against other tackles that he hasn't seen before. But this will be a great opportunity for him, because with all of the uncertainty at defensive end, look for the young guys such as Joe Jackson and Jelks to get plenty of opportunities.
Luke Gifford: I've been driving the hype train on Luke Gifford since OTAs/minicamps. I tend to fall in love with those players that show athletic ability and that's exactly what Gifford did for me. Since those early camps I was interested to see how Gifford would respond once the team starting practicing in pads. Jason Garrett likes to tell us that things aren't always perfect with the players but from what I have been able to observe up until this point Gifford's play has yet to fall off. Despite playing with a busted finger he is still taking his normal snaps both with the defense and on special teams.