Padres placed LHP Joe Thatcher on the 15-day disabled list, retroactive to July 26, with tendinitis in his right knee. Thatcher sat out all weekend because of the knee discomfort and hadn't made enough progress by Monday afternoon. The 30-year-old left-hander has posted a 3.42 ERA and 1.29 WHIP in 26 1/3 innings this season. He should be back within three weeks.