Ray Tanner doesn’t know much about service time or free agent clocks. But Tanner knows this: Jackie Bradley Jr. can handle the majors. “Without a doubt,” the former University of South Carolina baseball coach said by phone a few weeks ago, before Bradley began taking Red Sox camp by storm. “For me, the maturity — check; the ability to run bases — check; play defense — check; show up every day — check. Everything else, the press, the ability to play, he’s way beyond his years. Can he handle it? Absolutely.” So far, Bradley is doing his best to convince the Red Sox of that. Even after going 0-for-1 in yesterday’s 7-3 victory over the Minnesota Twins, he’s batting .517 (15-for-29) and has been the star of camp. Given the likelihood that David Ortiz will open the season on the disabled list, it’s conceivable the Sox would be best served by keeping Bradley as their primary left fielder and using Jonny Gomes as the designated hitter. For now, though, indications are the club would rather Bradley open the season in Triple A, a level at which he has not yet played.