Washington Redskins (1-4) at Arizona Cardinals (3-1)

Sunday, 4:25 p.m. ET, at University of Phoenix Stadium, Glendale, Ariz. – TV: FOX

*TV announcers: Dick Stockton, Brady Quinn, Kristina Pink

*Keys to the game: The secondary was supposed to be the strength of Arizona’s defense, but the Cardinals enter with the league’s 31st-ranked pass defense in large part due to the unit registering just four sacks through five games. The lack of pressure has left the secondary too exposed, and veteran CB Antonio Cromartie was repeatedly victimized by Denver last week. While Redskins QB Kirk Cousins found WR DeSean Jackson for two big gains against Seattle on Monday night, Washington needs to re-establish the ground game after RB Alfred Morris was held to 29 yards by the Seahawks. Arizona enters with the NFL’s fourth-ranked run defense.

Cardinals fans can’t feel buoyed by coach Bruce Arians’ declaration Wednesday that, “We’ll formulate a game plan to beat Washington and then see what quarterback’s available to be able to do that.”

With Carson Palmer (shoulder) and Drew Stanton (concussion) ailing, fourth-round rookie Logan Thomas took all the midweek reps with the first team. The coaching staff won’t admit it publicly, but Arizona’s offensive game plan will be significantly curtailed if the raw Thomas is forced into his first NFL start. Washington’s defensive weakness has been in the secondary, with S Brandon Meriweather particularly struggling in coverage, but will Arizona have a quarterback capable of exploiting him?

*Matchup to watch – Redskins RT Tyler Polumbus vs. Cardinals DE Kareem Martin: Coach Jay Gruden conceded that Polumbus has struggled in protection at times this season and while he is dealing with a dislocated finger, Polumbus is still far more reliable than backup Morgan Moses. The rookie Martin starts in place of Calais Campbell (knee).

*Player spotlight – Redskins LB Will Compton: A former undrafted free agent who made his NFL debut in last season’s finale, Compton could get his first career start if Perry Riley is sidelined by a sprained MCL. Riley has had his struggles in coverage, but is key to the run defense.

*Fast facts: The Redskins have four takeaways on the season. Only New Orleans (two) and the New York Jets (three) have fewer. … NT Dan Williams is the only healthy starter from the Cardinals’ starting front seven in 2013 expected to start Sunday.

WHO WILL WIN AND WHY

Much depends on who lines up behind center for Arizona. If it’s Carson Palmer or Drew Stanton, the Cardinals have enough firepower to exploit the Redskins’ undisciplined defense. If rookie Logan Thomas is forced into the equation, all bets are off even for the extremely resilient Cardinals.

*Our pick: Cardinals 20-16