The Scotland international goalkeeper, who had been sidelined for the previous two seasons with a career-threatening knee injury, made a series of magnificent saves to help the Scottish champions emerge with a point.
Celtic manager Deila was unstinting in his praise of Gordon, who looks set to prove an outstanding replacement for Fraser Forster after the England international was sold to Southampton last month.
“We had a fantastic goalkeeper tonight,” said Deila. “It was a marvellous performance from Craig. He has been good all season but tonight was really fantastic. He is progressing all the time. He is a top professional, a fantastic man and I’m so glad to have him at Celtic. I had only seen him on TV, playing for Sunderland, before I came to Scotland.
“Our goalkeeping coach Stevie Woods told me Craig was ready to play again and we now have a fantastic goalkeeper. He is working well with Stevie and he is going to get back to the level he was at before.
“He is proving people wrong who wondered about his fitness. He knows his body well and is very calm in his work. We had a great goalkeeper in Fraser but Craig has been a top quality replacement.”
Celtic were ahead twice, through Ghanaian winger Mubarak Wakaso on his debut and then captain Scott Brown. But Salzburg deserved their share of the spoils as they hit back with goals from Brazilian striker Alan and captain Jonatan Soriano.
Dinamo Zagreb are the early pace-setters in Group D after they romped to a 5-1 home win against Romanian side Astra Giurgiu in the other opening-night fixture. Celtic face the Croatian champions next, in Glasgow on 2 October, in what already promises to be a pivotal match in the section.
“I’m pleased with the point and happy with the performance,” added Deila. “We were playing against a very good team, they were very athletic and played with high intensity. Our players had to work their socks off and they did that.
“You can say it’s maybe disappointing not to win the match after leading twice, but I always try to look beyond the result. Salzburg had a lot of chances and our goalkeeper had to be fantastic. We did have a big chance to go 3-1 ahead which Anthony Stokes missed, but we got something from the game and I’m satisfied.
“Wakaso had a great debut and that was more than I expected from him at this stage. Scott Brown also got through 90 minutes and we also improved defensively as well, even if we had some problems on our right side in the second half.
“I think this team can only improve. I see possibilities here, I see the starting point of a very good team and that makes me happy. There were things tonight we could have done better, especially with the ball, but I saw a great team spirit which is also important and which helped us get a point. It is a good start for us in the group and we are looking forward to the rest of the matches.”