Sleith posted two strong performances as Robert Morris opened the season at the Hampton Inn Invitational in North Carolina. In the season opener against ACC member Virginia, Sleith allowed five hits and just one earned run in a complete-game effort. She struck out six Cavaliers and did not concede an extra-base hit during the contest. Sleith notched her first win of 2013 the following day against St. Bonaventure as she allowed three hits and one run while striking out nine in seven innings. For the week, Sleith compiled a 1.08 ERA while striking out more than a batter per inning pitched.