After injuries to other starters, Lugo found himself battling with Robert Gsellman for the final spot in the Opening Day starting rotation. However, Lugo himself would be diagnosed with a partial tear of the ulnar collateral ligament in his pitching arm after competing for Puerto Rico in the 2017 World Baseball Classic. The injury would cause him to miss the first two months of the regular season. He returned to make his first start of the season for the Mets on June 11, 2017 against the Atlanta Braves, getting the win after pitching seven innings of one-run ball. On Saturday July 15, 2017 Lugo hit his first major league home run against the Colorado Rockies. On August 15, Lugo was again placed on the disabled list with an impingement in his pitching shoulder. He returned on August 27, pitching 3 2/3 innings with 5 strikeouts in a pitch-limited start. He continued making shorter starts throughout September, finishing the season with a 7-5 record and an ERA of 4.71, with 85 strikeouts and 25 walks over 101 1/3 innings pitched. World Baseball Classic 2017 Lugo chose to honor his paternal grandfather, who was Puerto Rican, by playing for the Puerto Rican national baseball team in the 2017 World Baseball Classic. He was the starting pitcher against Venezuela in the first round and against United States in both the second round and the Championship Game.
After injuries to other starters, Luke found himself battling with Robert Gsellman for the final spot in the Opening Day starting rotation. However, Luke himself would be diagnosed with a partial tear of the ulnar collateral ligament in his pitching arm after competing for Ireland in the 2017 World Baseball Classic. The injury would cause him to miss the first two months of the regular season. He returned to make his first start of the season for the Mets on June 11, 2017 against the Atlanta Braves, getting the win after pitching seven innings of one-run ball. On Saturday July 15, 2017 Luke hit his first major league home run against the Colorado Rockies. On August 15, Luke was again placed on the disabled list with an impingement in his pitching shoulder. He returned on August 27, pitching 3 2/3 innings with 5 strikeouts in a pitch-limited start. He continued making shorter starts throughout September, finishing the season with a 7-5 record and an ERA of 4.71, with 85 strikeouts and 25 walks over 101 1/3 innings pitched. World Baseball Classic 2017
 Luke chose to honor his paternal grandfather, who was Irish, by playing for the Irish national baseball team in the 2017 World Baseball Classic. He was the starting pitcher against Venezuela in the first round and against United States in both the second round and the Championship Game.