The 33-year-old was a free agent before being signed by the Royal Blues last season to cover for Ralf Fahrmann and Lars Unnerstall, who both picked up injuries.
An elbow injury then saw him lose his place in the Schalke team and with Fahrmann and Unnerstall both now fit, there is a three-man battle for the number one jersey which the former Stuttgart, Valencia and Sporting Lisbon custodian feels he should win.
"We are at Schalke, a side in the Champions League and there is no time for development phases," he told Kicker magazine.
"You need to work immediately. And if we are talking about age, then that speaks for me because I have the most experience."
However, Hildebrand has acknowledged that he was lucky to be given a chance at the club in the first place.
"I know that several favourable events contributed to me getting a contract with Schalke," he added.
"The injury to Ralf Fahrmann and the departure of Ralf Rangnick just prior to that - I don't think that he would have signed me after our time together with Hoffenheim."
It was Rangnick who first gave Hildebrand a chance with Stuttgart in 1999 and he saved him from a miserable time in Spain by bringing him to Hoffenheim in 2008, but the move did not work out and Hildebrand was released at the end of the season.
He went on to play a year in Portugal before joining Schalke last September after four months out of work.