The heartache came late, but then Celtic's Champions League run this season has flashed through the emotional spectrum at such breakneck speed that there should have been no surprise.
A result that betters Benfica's at Barcelona in their final Group G clash with Spartak Moscow at Celtic Park next month will take them into the last 16, a position they would have willingly accepted before a ball was kicked in the competition, but last night it was almost so much more.
With 20 minutes remaining, they were through. Giorgios Samaras had scored in the 32nd minute to cancel out Ola John's early opener. They weathered storms from the skies and storms from their opposition, but then, with the game in the 71st minute, Ezequiel Garay smashed a volley into Fraser Forster's goal and ensured the nerves will fray until the final ball of the group is kicked. With five minutes to go, their talismanic figure Victor Wanyama was booked for a foul that will rule him out of their final game with Spartak.
It had not started well. By the seventh minute Celtic, rocked back on their heels, were behind. Eduardo Salvio seized possession, crossed into the middle and with Scott Brown unable to clear, Ola John shot so quickly that there was barely time for Forster to register as the shot flew past his right-hand side.
It was a lead that should have been doubled on the half-hour mark when Oscar Cardoza had only Forster to beat but dragged his shot wide of the near post. Within two minutes Celtic had drawn level. Charlie Mulgrew fired over his right-wing corner and with Gary Hooper holding his position next to Artur, Samaras was allowed to head into an empty goal from two feet out.
After the interval, Benfica had been giving plenty of warning of what they were capable of and in the 71st minute they delivered a second goal. The initial header came from Luisano, and it was perfectly placed for Garay to volley home.
Wanyama was denied by Artur in the 74th minute and from the rebound Kris Commons was denied. Salvio shot narrowly over Forster's crossbar and moments later Cardoza's free-kick was tipped over by the former Newcastle goalkeeper.