London, Feb. 13 -- Chelsea will be without striker Nicolas Jackson until after the next international break, leaving the club without a recognized "number 9" until the start of April.

The Senegalese forward, who has nine goals in the Premier League this season, tore his hamstring against West Ham a fortnight ago and although the club had hoped the injury was not serious, the BBC reports that scans have now shown Jackson could be sidelined for almost two months.

Chelsea also lost 19-year-old former Barcelona forward Marc Guiu in the same game after he suffered a groin strain after coming on to replace Jackson.

Chelsea coach Enzo Maresca has admitted Guiu will be out of action for "weeks or months."

The confirmation of Jackson's injur...