From 2009 through 2011, the Bengals had an odd situation at the left offensive guard position. In the 2009 playoff campaign, the Bengals switched back and forth between Nate Livings and Evan Mathis at the position. The stats clearly showed that Mathis provided the superior performance at the position, yet the Bengals stuck with Livings through last season until his departure to the Dallas Cowboys via free agency. Mathis left the Bengals via free agency after 2010.
Livings' performance has seemingly improved with Dallas, albeit marginally, while the Bengals moved on with Travelle Wharton and Clint Boling. In speaking with the Dallas media on Thursday, Livings said that he is "looking forward to his return to Cincinnati".
It's also important to note that Livings sustained a knee injury and was held out of practice on Thursday, though it doesn't appear serious enough to keep him out of the lineup on Sunday.