The Patriots will take the field for the first time in the preseason Thursday night against the Saints at Gillette Stadium. Here's what we'll be watching:

1. Rookies: The Patriots' top-three draft picks -- RDE Chandler Jones, SLB Dont'a Hightower and S Tavon Wilson -- should play a lot this evening, with Jones and Hightower in the starting lineup. Jones will get some reps against Saints LT Jermon Bushrod. Hightower will be tested by the Saints' TEs and RBs, and Wilson should fill several roles. A good test for the rookies.

2. Line woes: The Patriots' patchwork OL, with only LT Nate Solder playing in his projected spot, got handled by the Saints on Tuesday. But they are confident they've made the corrections. The line needs to keep QB Tom Brady upright against an aggressive front.

3. Deep coverage: The secondary was the Patriots' weak spot last season. CBs Devin McCourty and Ras-I Dowling and safeties Patrick Chung and Steve Gregory, need to show they've made progress with technique and competing to win the ball.

4. Mallett watch: QB Ryan Mallett didn't have a sharp preseason as a rookie, but that was after the lockout. With a full offseason, there are no excuses. Mallett needs to play fast and decisive and keep the team moving.

5. Undrafted rookies: The most impressive free-agent rookies have been RB Brandon Bolden and DE Justin Francis. Can they continue to their strong play and earn a roster spot when the games go live?

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