Chelsea’s Ghana midfielder Michael Essien injured his right knee in training this week, the Premier League club said on Friday.
“He will undergo tests over the next few days to determine the extent of that injury,” Chelsea said on their website (www.chelseafc.com).
Essien, 28, was sidelined for more than six months in 2008 with a cruciate ligament injury and missed last year’s World cup in South Africa with a knee problem.
Chelsea have also announced the appointment of former Nigeria international Michael Emenalo as their new technical director following his spell as assistant first-team coach for most of last season after Ray Wilkins left Stamford Bridge.
The club said the 46-year-old “takes on a wide-ranging, more senior role that oversees the club’s scouting networks, assists in driving the academy’s technical programmes and supports the work of first team manager Andre Villas-Boas”.