The USA international was omitted from Jurgen Klinsmann's initial 30-man squad for the finals in Brazil after sustaining a knee injury towards the end of the campaign.
"I feel very comfortable here at this club," he told the club's official website.
"I made friends here, I enjoyed playing football here this season. I was dealing with injuries again and again which is frustrating, especially at the end of the season.
"But everyone - the team, the staff, the players and the fans did their best. Now I am just focusing on my recovery so I can try my best to help the team go up next year."