Beram Kayal has urged his new Celtic team-mates to believe their three-goal Champions League deficit can be overturned -- because he did it last year.
Kayal, who signed a four-year contract yesterday, was part of the Maccabi Haifa team that looked like crashing out of the qualifiers when they fell 3-0 down in the first 15 minutes of the second leg against Aktobe after drawing away from home.
But they went on to reach the group stages, and the 22-year-old insists Celtic can do the same against Sporting Braga next Wednesday following their 3-0 defeat in Portugal.
Kayal, who must secure a work permit and is not available for the second leg, said: "We were three goals down in the first half at home to Aktobe from Kazakhstan.
"There were people crying in the stands when we went off at the interval because they thought we had blown our chance.
"But we came out in the second half and scored four times to win on aggregate.
"Everything is possible and nothing is impossible when you are playing in front of your home fans.
"Maccabi wiped out a three-goal deficit in 45 minutes. Celtic have 90 minutes plus the possibility of extra-time and penalties to get what we want."
While Kayal offered words of encouragement to his team-mates, Celtic defender Jos Hooiveld warned he felt like taking the opposite approach.
The centre-back, who missed most of the run-in last season through injury after his January signing, had to compose himself after being involved in the Portuguese disappointment.
"If I'd still been playing for my old club in Sweden, I'm sure I would have broken something after the game," the Dutchman said.
"At this moment at Celtic I have just come back from injury and people don't really know what kind of player I am.
"I'm not in a position within the group yet where I can go into the changing room and grab people by the throat. But I felt like doing it.
"This is my first chance to get into the Champions League and if we screw it up this way it would be frustrating. That is what bothers me most -- how easily we gave the goals away."