When American Marathon great and three-time US Olympian Meb Keflezighi steps to the starting line of this year’s TCS New York City Marathon on November 1st, this living legend will be representing the Un-carrier. Today, T-Mobile (TMUS) announced that the company will serve as an official sponsor of Meb as he runs his 10th New York City Marathon, as well as his historic bid to break the US Men’s Masters marathon record.