The 27-year-old lost his place to his compatriot after suffering an injury in January 2011 and has since struggled to regain his first-term berth, making just six appearances during the whole of the last campaign.
However, the Poland international has declared that he is ready to take on first-team responsibilities this term.
"It can change very quickly," Fabianski told the club's official website. "From my own experiences I know that, so I am ready to step up. I feel confident that I am able to be No 1.
|GUNNER DO IT
|11/1||Arsenal are 11/1 to win the Premier League with Sportingbet|
"Pre-season is always a fresh start, and it is hard work for us. We have to do all of the running and gym work too, it's not like we just have to do just goalkeeping! It has been good work over the past few weeks."
Fabianski also revealed that the club's keepers are working particularly hard on their positioning in pre-season, and that he is looking to improve on how he deals with crosses.
"At the moment I would say we are especially focusing - particularly us goalkeepers - on positioning ourselves in certain situations," Fabianski added.
"We are doing a lot of work with the 'vipers' that let us build up power in our legs, so everything that can help us improve.
"I didn't have too many opportunities to play last season but I am always focused and looking to improve, especially dealing with crosses because I think that is really important for a goalkeeper."