(973espn.com) - The Eagles take to the road for the first time this preseason for a Keystone State Battle against a Pittsburgh Steelers team that will be sitting most of its superstars.

So this is about work, not winning and losing, and it will be a key test for a number of Eagles players looking to impress the coaching staff as the slow march to the final 53 continues.

Here are the five Eagles you should be watching tonight:

No. 5 - Defensive End Marcus Smith - The former first-round pick returns to the lineup after missing the preseason opener with a concussion. During his absence, the unheralded Steven Means opened a few eyes with his ability to make plays especially on the pass rush. The new coaching staff seemed to be enamored with Smith’s skill set before his latest setback though and he's a better fit in Jim Schwartz’s scheme but at some point, he’s got to show something on the field.

No. 4 - Quarterback Sam Bradford - The Eagles starting quarterback will get his first extended action after a checkdown and two handoffs against the Bucs last week. The veteran talked about getting into a rhythm and that needs to start tonight with a wide receiver group minus its two most-talented options, Jordan Matthews (knee) and the recently acquired Dorial Green-Beckham.

No. 3 - Right tackle Allen Barbre - Barbre, typically the starter at left guard, will get the start at right tackle in front of the soon-to-be-suspended Lane Johnson and the veteran must prove he still has the athleticism to handle things on the outside. The Eagles seem to have a lot of confidence in Barbre and he has played both tackle positions in the past. That said, Johnson is one of the team’s four or five best players and there will be a drop-off, the question is how much?

No. 2 - Wide receiver Nelson Agholor - The second-year disappointment foolishly said the DGB trade wasn’t a message to the rest of the receivers but it most certainly was. The Eagles wanted Agholor to win the starting job opposite of Matthews but he continues to struggle getting off press coverage and he’s still far too inconsistent catching the football. If Green-Beckham’s presence doesn’t spark something, maybe there is nothing to spark.

No. 1 - Left Guard Isaac Seumalo - The Eagles know what they have in veteran interior backup Stefen Wisniewski so they are going to throw Seumalo, the rookie third-round pick, in the deep end of the pool during the rest of the preseason to see if he can swim. If Seumalo can’t handle things this early and he hasn’t been all that impressive this far, Philadelphia will simply look to Wisniewski to play the position once Johnson is suspended.

-John McMullen covers the Eagles and the NFL for 973espn.com. You can reach him at jmcmullen44@gmail.com or on Twitter @JFMcMullen