Van der Sar remains firmly in possession of the senior gloves as he approaches his 40th birthday next month.
"It was Edwin's decision to stay and he is a great goalkeeper and a good guy," Kuszczak told the Manchester Evening News.
"But I want to play in the first team. It has been difficult for the last couple of years because Edwin has been doing so well. He didn't make any mistakes and kept his position.
"It has been a good time for me to train with him and see how he goes about things. This is the experience I needed. I have learnt a lot and I want to play more and more. It is the only way for me.
"If I don't get enough games and the future is not going to be me then I will have to move.
"So long as the boss gives me a chance we will see how it goes. If I perform well I hope I will get more and more matches."