Islanders call up Christopher Gibson with Robin Lehner's status uncertainLehner suffered apparent head injury during collision Tuesday night3/6/2019, 9:57 PMMar 5, 2019; Uniondale, NY, USA; Ottawa Senators left wing Brady Tkachuk (7) is pushed over New York Islanders goalie Robin Lehner (40) by New York Islanders center Brock Nelson (29) during the third period at Nassau Veterans Memorial Coliseum. Mandatory Credit: Brad Penner-USA TODAY Sports / Brad Penner