Ireland captain Caelan Doris has been ruled out for a period of four to six months through injury, Leinster Rugby confirmed on Monday. The 27-year-old sustained the injury in the Irish province's Investec Champions Cup semi-final defeat to Northampton on 3 May. Last week, Doris was left out of the British and Irish Lions squad for this summer's tour of Australia by head coach Andy Farrell. The back row could now also be a doubt for Ireland's series of autumn matches against New Zealand, Japan, Australia and South Africa in November. An update from Leinster read: "Caelan Doris had a procedure on Friday last week for a shoulder injury which will keep him out of action for between four to six months." Doris had been a frontrunner to be named captain for the Lions tour, a role which was given to England second row Maro Itoje.