The 31-year-old striker has played just 187 minutes of football in six months, and has claimed that his international place with Wales could be in doubt.
"I need to play and be scoring 25 goals a season to play for my country. I want to play in the World Cup in Brazil. That is the biggest thing for me," Earnshaw told The Sun.
Earnshaw has scored 16 goals in 58 games for his country.