The New York Yankees placed relief pitcher Mark Leiter Jr. on the 15-day injured list on Tuesday, retroactive to Monday.The 6-foot, 210-pound righty, who lands on the IL with a left fibular head stress fracture, said he suffered the knee injury while covering first base during New York’s 5-4 loss against the Cincinnati Reds on June 24.The team did not provide a timetable for his return.The son and nephew of former Yankees pitchers Mark and Al Leiter, respectively, Mark Leiter Jr. is the latest New York hurler to land on the IL. Gerrit Cole is out this season due to Tommy John surgery, and Clarke Schmidt will undergo the same surgery after forearm soreness built up in recent weeks.What’s more, Leiter’s injury comes amid a stretch during which the Yankees have struggled, losing 16 of 23 games.