In this Dec. 16, 2012 file photo, Miami Dolphins tackle Jonathan Martin (71) watches from the sidelines during the second half of an NFL football game against the Jacksonville Jaguars, in Miami. (AP Photo/Wilfredo Lee, File) by Paul NewberryAP Sports Columnist To his Miami Dolphins teammates, Jonathan Martin came across as someone who needed "toughening up." But what does that mean, exactly, when you're talking about a 6-foot-4, 320-pound guy who already had proven he was tough enough to play a violent, brutal sport at the highest level?
