The 32-year-old left Manchester United to join MLS side Chicago Fire in March earlier this year. In a recent interview, he admitted that he is yet to adjust to the football with his new side, which finished bottom of the league last season.
The World Cup-winner told Suddeutsche Zeitung: "We all know that this league is just not like the Premier League or the Bundesliga and, of course, it can be frustrating on the pitch at times when things discussed are not implemented or when somebody loses a ball or just does not have an eye for the team-mate.
"I don't blame anyone for it, that's my problem – I need to adapt to the league and cope with those situations.
"If you compare it to Bayern Munich or the national team, the difference is huge, but I knew what I let myself in for."
The former Bayern Munich midfielder added: "The league is interesting because sometimes things happen you just don't understand. This might be referee decisions or the running paths or passes of a team-mate."