In February, Sock returned home to the United States where he helped the Davis Cup team sweep their 1st-round rubber against Switzerland. At the end of the month, he played at the Delray Beach Open and won his second title in two months after Milos Raonic withdrew from the final with a hamstring injury. This title took Sock to a career high of 18 in the ATP rankings. Sock continued his impressive streak of deep runs in Masters events by reaching his first career Masters semi-final at the BNP Paribas Open in Indian Wells. Along the way, he upset No. 13 Grigor Dimitrov and No. 5 Kei Nishikori, the latter of which was his first career victory over a Top 5 opponent.