"I will not be coming back for the 2014 season I have decided to move on to the NFL and declare for the draft," Martin said Friday via his Instagram account. "Thank you Trojan Family for all that you've done for me ! This will be a season I will never forget as long as I live and I wanna thank the coaches my teammates and the fans for all that we've endured as a family ! I am and always be a Trojan for life #FightOnForever"
Martin started ten games at left guard as a freshman and followed his strong debut season with a solid sophomore campaign at left guard as well.
Former coach Lane Kiffin moved Martin to center for the 2013 season since the graduation of center Khaled Holmes.
Martin started all 13 regular season games at center for the Trojans as a junior, but was forced to sit out in their 45-20 win over Fresno State at the Las Vegas Bowl. He injured his knee in the first quarter of the Trojans regular season finale against UCLA and was carted off the field.
New USC coach Steve Sarkisian's offensive line could become even thinner in the coming days; right guard Aundrey Walker is also expected to make himself available for the draft.
Safety Dion Bailey announced Monday he will leave early for the NFL, too.