Karlsson won the 2015 James Morris Memorial Trophy for the NHL's top "defense player who demonstrated throughout the season the greatest all-around ability in the position." This is Karlsson's second time taking home the trophy, as he won it back in 2012 as well. The captain recorded a team-high 45 assists over the course of the regular season en route to leading the team in points with 66. Karlsson also was the most durable player for the Senators this season, playing in all 88 games.