Today marks the arrivals of the defensive backs to the combine, but since the Patriots aren't really in the market yet (I'm still under the impression that Darrelle Revis and Devin McCourty will both sign back), hopefully New England won't need to look at these players early on.
As for the quality of the defensive backs, there aren't many good safeties this year, while the cornerback market is a little thin. The top cornerbacks this year aren't as highly rated as in years past.
Still, there will be plenty of news surfacing as drills start today!
The offensive line and tight ends will be running drills and performing speed measurements.
The quarterbacks, wide receivers, and running backs will throw up some bench press numbers.
The defensive line and linebackers will be measured and weighed.
The Patriots will meet with players.
We'll keep track of the highlights in this thread. Chime in if you hear anything!