LONDON (REUTERS) - Manchester City's Argentinian full-back Pablo Zabaleta will be out of action for at least a month after injuring a knee in training, the club's website reported on Friday.

He could miss up to six games.

"It happened in training," Zabaleta confirmed. "It's the first time in 12 years of senior football that I've ever been injured like this so it's a blow, especially at the start of the season."

The injury leaves Bacary Sagna as City's only senior right-back.

Left-back Gael Clichy and midfielder Fabian Delph returned to training this week, though it is not known if they will be considered for Sunday's Premier League game at Everton.

City go into the weekend top of the table on goal difference after winning both their opening games 3-0.