Chelsea have announced an investigation into whether an object was thrown at an injured steward during their defeat to Manchester United.
The steward was hospitalised with a twisted knee, having injured himself after slipping on the turf following Javier Hernandez's winning goal in Manchester United's 3-2 victory at Chelsea's home ground.
Roberto Di Matteo laid the blame for his Chelsea side's 3-2 defeat to Manchester United firmly at the door of referee Mark Clattenburg.
The official sent off Fernando Torres for what he deemed a dive midway through the second half, while TV replays suggested Javier Hernandez was offside when he scored the winner for the Red Devils.
Manchester United climbed to within a point of the league summit with a 3-2 victory over nine-man Chelsea at Stamford Bridge.
Roberto Di Matteo's team recovered from 2-0 down to make it 2-2 early in the second half but had Branislav Ivanovic and Fernando Torres sent off before substitute Javier Hernandez scored a 75th minute winner from what appeared to be an offside position.
Wayne Rooney has warned his Manchester United team-mates they cannot afford to concede an early goal against Chelsea on Sunday.
Chelsea recruited Oscar and Eden Hazard in the off-season for a combined fee of almost 60 million pounds, joining Juan Mata in attack playing just behind Fernando Torres - and the combination has proved to be formidable so far.
Chelsea manager Roberto Di Matteo has launched a passionate defence of his under-fire Spanish striker Fernando Torres.
The 50 million pounds record signing for the Blues has scored six goals in 12 games this term with his team top of the table, and his boss thinks criticism of the 28-year-old is misplaced.
Roberto Di Matteo has targeted Manchester United's defensive problems as key to Chelsea's chances in their 'massive' clash on Sunday.
The Blues are currently sitting at the summit of the Premier League table with 22 points - but Manchester United are just four behind them in second.
John Obi Mikel wants Chelsea to respond from their loss to Shakhtar Donetsk by beating Manchester United in Premier League action on Sunday.
Shakhtar inflicted Chelsea's first competitive defeat of the season on Tuesday, and Mikel is hoping Roberto Di Matteo's men can work on their defensive solidity before they host United to prolong their unbeaten league run.
Patrice Evra believes Manchester United are beginning to hit their best form but says they will have to work hard to overhaul Chelsea.
United travel to Stamford Bridge on Sunday to take on Roberto Di Matteo's Premier League leaders knowing a victory will close the gap to just one point ahead of the visit of Arsenal six days later.
League leaders Chelsea host Manchester United on Sunday in a clash that could have a major bearing on the outcome of the title race.
Chelsea have won seven of their opening eight matches to establish themselves as the team to beat in the English Premier League, despite their shaky form in the Champions League.GOAL.COM - Global football news, transfer rumours and betting editorial
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