The Lions have signed offensive guard Rob Sims to a four-year contract extension. Sims, who earns a base salary of $1.2 million this season, is now under contract with the Lions through 2014. "We don't do a lot of renegotiating during the season, but in this case it just made sense," said Lions president Tom Lewand. "Rob is a young guy who has really solidified our offensive line." "We liked Rob for a lot of reasons when we traded for him and he has validated all the things we saw," Lewand said. "He's been a great fit in the locker room and a great fit schematically on the field."