The 33-year-old goalkeeper was busy in a 3-3 draw, his first taste of the Champions League group stage.
Having been the number one choice for the past two seasons, Gordon was playing after Dorus de Vries picked up an injury at the weekend.
"I was happy with how I played - that's all I can do," he said.
"Everybody wants to be a part of nights like that. There is no bigger incentive to play well and keep your place."
Former Hearts and Sunderland keeper Gordon started the first nine matches of the season but lost his place to summer recruit De Vries in mid-August.
Gordon was a half-time replacement in Saturday's win over Kilmarnock, with the 35-year-old Dutchman suffering a chest injury.
De Vries was fit enough to be among the substitutes in a thriller with Manchester City in which Gordon made two good stops to deny Ilkay Gundogan, one late in the game from a deflected strike.
"This is the highest level of club football and to finally manage that at the age of 33 is a special moment for me," said Gordon.
"We'd have liked to get the three points but it was an incredible effort against a top quality side."
Asked how the match ranked in his long career, he replied: "It's right up there. The atmosphere was just incredible.
"The noise was unbelievable. There was a couple of times when I was absolutely screaming at Kolo [Toure] to leave the ball and he just couldn't hear me. I couldn't have shouted any louder."
Gordon, capped 44 times for Scotland, insists his self-belief has not wavered since dropping to the bench and is hoping manager Brendan Rodgers will find it difficult to reinstate De Vries.
"I've always been confident in what I'm able to do," he added. "It was other people saying my confidence was gone.
"If I've not been selected, that's the manager's decision and I fully respect that.
"The other side of that is that I want to play every game.
"I think I've done pretty well in stages this season and if I can get a run in the team then hopefully I can go from strength to strength."

The discovery was made after another child was threatened in the school's playground on 4 March.
A boy was excluded from the school following the incident, in which no-one was injured.
A police spokesman said the child was spoken to and reported to the Reporter to the Children's Panel.
He added: "No-one was injured in the incident and a knife was recovered."
Dumfries and Galloway council described the behaviour as "totally unacceptable".
A spokesman said the local authority took safety in its schools very seriously.
He added: "The school carried out investigations immediately and handled the matter appropriately and sensitively, involving the parents of the children concerned and Police Scotland.
"The incident resulted in an exclusion, with arrangements in place between the pupil, parents and the school in terms of expectations, support and supervision.
"The council is providing support, advice and resources to assist the school deal with this matter."

Mazembe made sure of the win having held their opponents to a 1-1 draw in Algeria in the first leg of the final last weekend.
They won the final 5-2 on aggregate, to add the Confederation Cup to their list of honours after winning the African Champions  League in 2015.
On Sunday, Mazembe went ahead in Lubumbashi after just seven minutes through Merveille Bope who reacted quickest to a Jean Kasusula free- kick which hit the woodwork.
Zambia international Kalaba (pictured) hammered home a volley on the stroke of halftime to make it 2-0 and scored again just after the hour mark to put the result beyond the Algerians, appearing in their first continental cup final.
Bejaia scored a consolation goal in the 75th minute from Sofiane Khadir but the three-goal advantage was restored within 60 seconds by Jonathan Bolingi.
Mazembe were eliminated early in the defence of their African Champions League trophy this year and dropped down to the continent's second tier club competition.
They will receive $660,000 following their Confederation Cup triumph with Bejaia receiving the runners-up prize of $462,000.
Mazembe will now play this year's African Champions League winners, Mamelodi Sundowns of South Africa, in the 2017 African Super Cup on the weekend on 17-19 February.
Craig Gordon hopes an impressive display against Manchester City can help him retain a regular starting position at Celtic.
[NEXT_CONCEPT]
Police were called to a primary school in Dumfries after a nine-year-old pupil was found with a knife, it has emerged.
[NEXT_CONCEPT]
Zambia international Rainford Kalaba scored twice as TP Mazembe of the Democratic Republic of Congo beat Algeria's Mouloudia Bejaia 4-1 at home on Sunday to win the African Confederation Cup for the first time.