San Diego Padres catcher Ramon Hernandez was placed on the 15-day disabled list after undergoing surgery on his injured left wrist Friday. Hernandez, who opted for surgery after getting a second opinion that confirmed a cartilage tear in his wrist, is expected to miss up to six weeks of action. The Padres catcher suffered the injury in a June 17th contest against Minnesota and spent time on the disabled list. He is batting .273 with seven home runs and 38 RBI in 76 games this season. San Diego acquired Hernandez in November of 2003 from Oakland. He is eligible for free agency after this season. To fill the vacant roster spot, the Padres activated catcher David Ross. Ross was just acquired Thursday after the Padres traded minor league shortstop J.J. Furmaniak. In other team news, San Diego placed reliever Chris Hammond on the 15-day disabled list with a strained neck and recalled lefthander Craig Breslow from Double-A Mobile. Hammond went 5-1 with a 2.96 ERA in 37 games for the Padres this season.