Dean Gerken has produced some memorable man-of-the-match displays for Bristol City this season, none more so than his trip to St James' Park.

The former Colchester goalkeeper kept a magnificent clean sheet against Newcastle United in October – but that doesn't tell the full story.

Gerken wasn't due to play against the recently-relegated Magpies as he had been out of the team because of illness for almost a month. Indeed, he wasn't even expected to be on the bench.

But when Adriano Basso pulled up lame while warming up in front of the Gallowgate End, manager Gary Johnson chose to bring in Gerken rather than press the inexperienced Stephen Henderson into what would have been the biggest game of his career – and the 24-year-old went on to deny Marlon Harewood, Peter Lovenkrands and Alan Smith with a series of impressive saves.

Gerken believes that the short notice he was given actually helped his performance.

Speaking ahead of Newcastle's visit to Ashton Gate tomorrow, he said: "It is the first time that has happened to me but five minutes before kick-off Basso was declared unfit.

"In a funny way, it was a good thing because I didn't have much time to think about it.

"It was my first game for three weeks after illness so it was probably the perfect way to be pushed into such a big game. Luckily, we got a good result up there and hopefully we can do it again on Saturday."

City will be firm underdogs tomorrow – and the feeling is that when they are in that situation the Robins tend to hit form.

"It might not be a good thing to say, but against the bigger teams we always seem to perform and that is when you see Bristol City play their best football," said Gerken.

"It will be a hard game against Newcastle – they have a massive chance of going up, especially with the money behind them.

"But we have to go out there and believe in ourselves because if we go out and play well we are not going to be far away against any team in this league."

With Basso having left Ashton Gate following the settlement of his contract, Gerken is now well established as the club's No 1 keeper.

"Maybe it was through default, but I think I have taken the opportunity I was given at the beginning of the season as well as I possibly could and I am really enjoying being a number one at such a good club," he said. "Goalkeeper is probably the hardest position to play in terms of earning thanks for your performance.

"Week in and week out you have to do your job and make sure as many balls as possible are kept out of the net and keep your team in with a chance of winning the game – but make one mistake and everyone jumps on it."

Defeat at Plymouth on Tuesday realistically ended City's lingering play-off hopes, but Gerken believes there is still plenty to come from the Robins' squad.

"We are mostly a young squad and a developing squad," he said. "We have some great players and some great ability in the team and now it is about fulfilling that and pushing on to the Premiership.

"Our ambition between now and the end of the season is to get as many points on the board as we can and see where we end up."