Cooper Cronk underwent a shoulder surgery and is expected to miss the Melbourne Storm's trials and is questionable when round one begins in the National Rugby League (NRL).

"He has had an operation on his shoulder so that is the main reason he won't play in any of the trials," said Storm coach Craig Bellamy. "And I'm not quite sure he will be ready for round one."

According to reports, the 30-year old playmaker was already playing through the injury in the latter part of 2013 and aggravated it during the World Cup.

The Storm finished at 16-7-1 in 24 games in the premiership in 2013 for 3rd place overall. Cooper played in 23 games in 2013 and finished with 19 points, 3 field goals, 4 tries and 381 tackles.

He helped the Storm to the NRL premiership title in 2012, when he had arguably the best statistical season of his career.

Cooper also played 15 Tests for Australia from 2007 to 2012.

The Melbourne takes on Canberra in their first trial on Feb 8, Saturday, at AAMI Park.