The Smurfs have been left a little blue after learning their hit family film didn't quite have the pulling power at the U.S. box office to share the top spot at the weekend. 

Initial estimates suggested the film had tied for the number one slot with action blockbuster Cowboys & Aliens - but official figures have the little blue men in second place. 

Harrison Ford and Daniel Craig's film have edged ahead, claiming $1 million more than The Smurfs at the U.S. box office. 

Cowboys & Aliens romped to the top of the charts with a $36.4 million opening weekend take.