I’ve written many times, including earlier Thursday, that New Orleans Saints running back/return man Darren Sproles has turned out to be the best free-agent signing of 2011.

There are some other good candidates out there. AFC South colleague Paul Kuharsky makes a case for Houston Texans cornerback Jonathan Joseph. There’s no doubt Joseph was a great signing and his impact on the defense is a reason the Texans are in the playoffs for the first time.

You also could make a case for Philadelphia defensive end Jason Babin, Denver running back Willis McGahee or Tennessee quarterback Matt Hasselbeck.

My vote still goes to Sproles. I think his presence has taken a very good New Orleans offense and made it into one of the best in history.

But let’s hear your thoughts. Take a look at the SportsNation poll to the right and cast your vote. Then, feel free to back it up in the comments section below.