In-form Shane Sutherland bagged a brace as Peterhead extended their unbeaten Scottish League One run to 17 games with a 4-1 win at Stenhousemuir.Peterhead took the lead in the 13th minute when Jamie Stevenson - who was forced off injured 15 minutes later - fired left-footed into the bottom corner.Sutherland then claimed his 10th goal in 12 games two minutes before half-time after being set up by Ryan Strachan.He added a second in the 54th minute from the penalty spot after keeper Colin McCabe had fouled Leighton McIntosh, who fired in a fourth in the 67th minute.Substitute Lewis Small hit the crossbar for Stenny, who pulled a goal back with nine minutes remaining through Carlos Martinez as they fell to a third successive defeat.