By Dominic Toner

Chelsea could be without defender Branislav Ivanovic for their opening Premier League clash against West Ham, according to a report.

The Serbia international sustained an injury during a pre-season game against RZ Pellets and is now facing a spell on the sidelines.

The Mail report that Ivanovic dislocated his shoulder in the match and is expected out for three weeks, meaning it will be unlikely he has returned to full fitness by the middle of August.

West Ham travel to Stamford Bridge on 15 August for their opening league fixture and with their opposition missing a senior defender they could hold a slight advantage.

Right-back Ivanovic has been a key player for Chelsea since his move from Lokomotiv Moscow in 2008 and has made over 300 appearances for the London club.

Last season West Ham were unbeaten against Chelsea in the league, winning 2-1 at home in October and holding them to a 2-2 draw in the reverse fixture.

Slaven Bilic helped the club to a seventh-placed finish and guaranteed European football this season whereas the previous reigning champions slumped to tenth in the league.

New manager Antonio Conte will have plenty of replacements to fill the Ivanovic void and could hand youngster Ola Aina a starting place at right-back.

West Ham do have their own injury problem to contend with as their left-back Aaron Cresswell picked up a knee injury in a pre-season 3-0 victory over Karlsruher SC.

Their website report that they are currently monitoring how bad the injury is but will be hoping it is not too serious, as he started 37 of their 38 Premier League matches last season.

In other West Ham team news, their new signing has set himself a target for the upcoming season.