Cech Azpilicueta, Cahill, Terry, Bertrand Lampard, Ramires Marin, Mata, Oscar Torres
Brentford manager Uwe Rosler will be without on-loan Everton defender Jack Bidwell for the visit of European champions Chelsea, after the youngster was sent off in Tuesday's 2-2 draw with Leyton Orient.
Veteran midfielder Kevin O'Connor (ankle) will also be out, as is Farid El Alagui (knee).
Harry Forrester was rested against Orient in the week, and he should return along with Fulham loan star Marcello Trotta and defender Shaleum Logan.
Chelsea will be without Belgium attacker Eden Hazard as he starts a three-game ban following his controversial red card for kicking a ballboy at Swansea on Wednesday.
Captain John Terry may make a first start following his steady recovery from a knee problem but Rafa Benitez will be without Yossi Benayoun and Oriol Romeu (both knee).
DID YOU KNOW?
Brentford currently lies third in League One, six points behind joint leaders Tranmere and Doncaster Rovers.
The Bees have only reached the fifth round of the FA Cup on six occasions since the Second World War.
Striker Clayton Donaldson is second in the League One scoring charts this season - he has 15 strikes. He is also joint-second in the scoring charts for the FA Cup, with four goals in this season's competition.
Chelsea will have played its west London neighbors Fulham, QPR and Brentford in the same season for the first time ever following this cup tie.
The Blues are the current holders of the FA Cup, having defeated Liverpool 2-1 in last year's final. They have won the competition on seven occasions.
Of all the Premier League players to score more than five goals this season, Chelsea midfielder Frank Lampard (pictured, right), has the best conversion rate (42 per cent).
Brentford and Chelsea are separated by just six miles, but have not played each other competitively since meeting in this competition 63 years ago.
Brentford's Griffin Park stadium famously has a pub on each of the four corners of the ground. Supporters may be pushed for time to frequent all of them before Sunday's game, however, with kick-off set for 12:00.