Genoa left-back Luca Antonelli will miss up to a month of the season due to the injury he suffered in Italy's 1-0 win against Bulgaria on September 6.
Antonelli left the Italy squad and did not take part in the 2-1 win over the Czech Republic on Tuesday night, and the club have now confirmed that it is ankle ligament damage.
"The prognosis is expected to be three to four weeks," the club said in a statement.
Antonelli joined Genoa in 2011 from Parma.