Lancaster remained with Louisville and made his season debut against rival FC Cincinnati on 7 April, when he scored the game's only goal. Although slowed by injury during the season he still appeared in 30 of Louisville's 34 league matches and lead both Louisville and the league with 25 goals; a USL single season record. This included scoring his first Hat-trick as a professional on 8 October against New York Red Bulls II. He also appeared in four of Louisville's five U.S. Open Cup matches as Louisville reached the quarter finals of the competition for the first time in its history. This included a 3–2 victory over the New England Revolution of MLS; Louisville's first victory over an MLS side. He along with Brian Ownby lead the team with two goals scored in the competition including a goal against New England. Lancaster also appeared in three of Louisville's four USL Cup playoff matches scoring one goal. During the Eastern Conference Final match against New York Red Bulls II he was injured and was unable to play in the USL Cup final against Phoenix (a match that Louisville went on to win). Lancaster finished the season winning the USL Golden Boot and being named to the USL All League First Team. He along with Ilija Ilić were the only Louisville players to score at least ten goals in league play while he, Ilić, and Luke Spencer were the only Louisville players to score a goal in all competitions.
