The Pirates have placed first baseman Adam LaRoche on the 15-day disabled list with a right strain of his ribcage muscle. Infielder Brian Bixler was recalled from Triple A-Indianapolis to take LaRoche’s place on the 25-man roster. Doug Mientkiewicz will make his second consecutive start at first base in place of LaRoche, who is one of the hottest hitters in the NL in July, batting .390 with seven home runs and 18 RBI. Also, second baseman Freddy Sanchez is out of the lineup for tonight’s 7:05 game with the Colorado Rockies at PNC Park. Sanchez, who suffered back spasms on Sunday, is out until at least Friday, manager John Russell said.