The German goalkeeper was a 56th minute substitute after Ederson was injured in his challenge on Darwin Nunez.
It was a difficult moment to enter the match with Anfield pushing their team forward in search of a winner.
But Ortega made a number of big saves to remain unbeaten, including an excellent stop to deny Nunez, and the number 18 said he enjoyed playing his part.
“If you are on the bench, you always think about what can happen if you go on the pitch,” he said.
“[Against Liverpool] was my time with Eddie’s injury. I was ready like always.
“It was a special moment to come on in this big game and the whole world watching. It was a nice feeling.”
It’s the second time this season that Ortega has come off the bench after replacing Ederson in the 3-2 win over Newcastle in January.
He has started all of our FA Cup matches since joining the Club in the summer of 2023 so is likely to continue when we face the Magpies for a fourth time this season on Saturday in the sixth round.
Along with Scott Carson, the goalkeeping unit work hard in training and Ortega says it’s the same task whether he starts or comes on.
“Just do my job,” he added about his thoughts on his second half introduction against Liverpool.
“I do it every day in training and it was about doing the same. I enjoyed every second. It’s nothing new what came - I was ready and prepared.”
The draw makes the title race even closer with Arsenal now top on goal difference with City in third just a point behind.
Ortega says either side could have won Sunday’s clash in what was a thrilling encounter.
“It was a solid performance. I enjoyed it - a good atmosphere and opponent,” he said.
“[It was] a tough game - it’s not easy to play against Liverpool, especially here.
“One point is good - both teams had chances to win but in the end it was even.
“Both teams played really well, and I think it was a good game to watch on the outside. One point is better than no point.”
