Red Sox shortstop Stephen Drew, out since March 7 because of a concussion, was cleared to play by Major League Baseball and played in an extended spring training game in Florida Tuesday. Drew played three innings in the field and was 1 for 3 with a double. It was a major step for Drew, whose spring training came to a halt when he felt dizzy and had problems with his vision after being hit in the head with a pitch. Drew was cleared to start baseball activities March 17 but needed further testing to get in games. Because Drew had only 18 plate appearances before he was injured he likely will need at least a week of games to get prepared. He is eligible to come off the seven-day concussion disabled list Wednesday. Jose Iglesias started at shortstop on Opening Day for the Sox and had three infield hits. Iglesias has shown great improvement this season at the plate. But Drew, who was signed to a one-year, $9.5 million deal, will be the starter once he is deemed ready.