newbee needs help with matching.

GLOBAL_ShippingAddress:
John Smith
The Smith Company
18815 Main St
Beaverton, Oregon 97006
United States

javascript:
var FullAddress = "%%GLOBAL_ShippingAddress%%";
var matches = FullAddress.match(/[^0-9]([0-9]{5})/);
document.write('matches: '+ matches + '<br>');

output:
matches: 90291,90291

I need the output to be 90291

I have no idea how to alter the FullAddress.match(/[^0-9]([0-9]{5})/); to output just one zip code, any help would be appriciated.

Thanks,