Melbourne Heart coach John van 't Schip believes the length of the A-League's pre-season is affecting the quality of the competition.

The Dutchman is not used to the environment in which the A-League off-season lies and although he accepts that the sport has to compete with other codes, feels that such a long preparation makes it tough on the players.

"It's the way it is. You can say it's good, it's bad but the only thing that I can say is it's not good for the league," he told au.fourfourtwo.com.

"It's not helping; it's not helping at all. It's not good if you want to be a serious competition.

"Next season we will have five months off and that can never be good for the soccer [in Australia]," he added.

"If you want to make it clear to the outside world that we're taking soccer serious in Australia, then they should make the league more extended with a league of nine months and a three month off-season."