Dioner Navarro will be on the Dodger disabled list when the 2011 regular season begins and likely remain out until the end of April because of a right oblique tear. Tony Jackson of ESPNLosAngeles.com has details.... Mattingly said A.J. Ellis and Hector Gimenez will compete during the handful of days left before Opening Day for the right to hold down the backup catching job until Navarro returns. But Mattingly also hinted that Barajas might draw almost all of the starts while Navarro is out. Although Barajas is 35 and Mattingly had planned to give him regular rest, that rest presumably isn't as important in April."We're looking at Rod as the primary guy," Mattingly said. " I know I have to keep him strong, and I know he is an older guy. But I love his leadership. Earlier in the seas