Croydon-born Sean was scouted by Palace at the age of 14 and has represented Republic of Ireland at under 21 level, qualifying through his father.

After scoring 23 goals for the academy during the 2006/07 season, Sean continued his progress, becoming a regular member of the reserve and U18 squads.

Sean is a speedy forward with a light touch, who came to the attention with a last-minute winner against Sheffield Wednesday on 15^th December 2007.

The inch-perfect chip sealed a 2-1 win for Palace in only Sean's third substitute's appearance as a 17-year-old.

He then went on to cement his reputation as one for the future with impressive starting displays, both as a forward and a right winger. On 8^th January 2008 he was rewarded with a two-and-a-half-year professional contract.

Scannell finished that season with 23 league appearances, and built on that steadily over the next two seasons, each time notching up a few more games under his belt.

In the 2008/09 season he finished with 25 league appearances, and then added to it further with 26 games in the following season. That achievement was recognised and Sean was named the 2009 Young Apprentice of the Year at the end of season Football League Awards ceremony.

Ahead of the 2010/11 season, Sean suffered a knee injury that forced him out for six months, and he did not return until the New Year. Sean managed 19 league appearances upon his return, scoring twice.