Peter Millar may be best known for sponsoring a number of high-profile professional golfers, including Sam Burns, Cameron Young and Justin Rose. But now the Raleigh, N.C.-based brand has moved beyond the links to the gridiron, signing its first NFL ambassador: Christian McCaffrey, the running back for the San Francisco 49ers. “Christian represents the kind of multidimensional excellence that defines Peter Millar today,” said Scott Mahoney, the brand’s chief executive officer. “It’s an honor to join the Peter Millar family,” McCaffrey said. Jason Cater, chief creative officer of Peter Millar, said: “From the beginning, Peter Millar has approached performance with a sense of refinement.