Mohamed Elyounoussi scored a brace in the first half to give Celtic a shock 2-0 lead over the home side in France, but Zeki Celik and Jonathan Ikone netted goals after the break to level things up.
Lille dominated the game with 72 per cent possession, but Celtic were in with a chance to take three points at half time at the Stade Pierre Mauroy.
Stewart has admitted that Celtic would have easily taken a draw at the start of the game, but conceded that it seems like a squandered opportunity as they led 2-0 at half time.
But the former Scotland star feels the Bhoys will have a lot of positives from the trip to France for their trip back home to Scotland.
Stewart said on BBC Sportsound: “Celtic would have taken a draw before the game.
“Looking at the dynamic of the game it’s disappointing to lose the lead.
“But there are lots of positives for Celtic to focus on.”
Celtic will be in action in the Scottish Cup semi-final against Aberdeen on Sunday, as they look to return to winning ways.
