AlQa'dah 6, 1435, Sep 1, 2014, SPA -- Serie A side Fiorentina have signed four new players on the closing day of the transfer market as they announced that striker Giuseppe Rossi is to undergo knee surgery, dpa reported. The Florence club said Monday that the 27-year-old international was examined in London and was to be operated on his right knee this week. Rossi, who twice tore the cruciate knee ligament and underwent three operations while at Villa real, hurt the joint again during a league game with Fiorentina in January. He was at the time the Serie A top scorer on 14 goals, but failed to fully recover for the World Cup that Italy played in June in Brazil. He is now expected back on the pitch in about two months. With their best striker out in the first part of the season and after suffering a 2-0 defeat in Saturday's league opener at Roma, la Viola completed four deals before the closure of the transfers window late Monday (2100 GMT). Croat midfielder Milan Badelj from Hamburg 4.5 million euros (5.9million dollars) and his compatriot defender Ricardo Bagadur. English defender Micah Richards was signed from Manchester City, and Slovenian midfielder Jasmin Kurtic arrived on from Sassuolo.