 On 26 October, Gustavsson recorded his first NHL win against the Anaheim Ducks, making 25 saves on 28 shots in a 6–3 win.After overcoming a groin strain, on 1 December, Gustavsson left after the first period in a game against the Montreal Canadiens with a heart murmur, which led to a second Radio Frequency ablation to treat a reentrant tachycardia.After he was cleared to return, he responded by recording his first NHL shutout in a 2–0 win over the Boston Bruins on 19 December.