France number one Gael Monfils is injured and will miss his country's Davis Cup semi-final against Spain in Cordoba from September 16-18. Monfils, writing on his facebook page, said: "I had some tests this morning after a problem with my right knee. I've got a swelling and will be sidelined for a fortnight. Unfortunately I can't play in the Davis Cup." The news comes 24 hours after he was named in the France team alongside Jo-Wilfried Tsonga, Gilles Simon and Richard Gasquet. Doubles specialists Michael Llodra and Julien Benneteau will also travel to southern Spain, with captain Guy Forget having until the day of the draw, on September 15, to make changes to his line-up. Forget is likely to introduce at least one of Llodra and Benneteau at the expense of one of his singles specialists, with Monfils out and Gasquet nursing a shoulder injury. World number two Rafael Nadal is to return for Spain alongside David Ferrer, Fernando Verdasco and Feliciano Lopez. France beat Spain 5-0 in the quarter-finals in Clermont-Ferrand last year before losing in the final to Serbia.