Production at tight end for 49ers goes beyond Vernon Davis

A big part of the San Francisco 49ers' offense the past few seasons will be playing against them Sunday for the Tennessee Titans.

But an emerging San Francisco attack appears to be absorbing the loss of Delanie Walker well at the tight end position, and it's not just the exploits of starter Vernon Davis.

Rookie Vance McDonald has played well as the new No. 2 to Davis and veteran Garrett Celek also has contributed in an offense that uses two tight-end formations often, just like it did when the versatile Walker was lining up at multiple positions the past two years for offensive coordinator Greg Roman.