Last Updated: 27/01/13 1:54pm
FULL-TIME: The referee brings the game to an end and Brentford have earned a replay against FA Cup holders Chelsea with Fernando Torres' late goal denying the home side a famous FA Cup win.
Strong claims for a penalty from Chelsea as Mata's cross appears to strike the hand of Dean inside the box, but the referee waves away their appeals.
Ramires is penalised for handball. Chance for Brentford to get some numbers in the box from the free-kick.
Mata picks out Lampard inside the box, but he gets his header all wrong and it loops up into the air and into the grateful arms of Moore.
Lampard has a crack at goal from 25 yards out and Moore is alert to save the effort at the second attempt.
GOAL: Chelsea draw level for a second time as the ball drops to Torres on the edge of the box and he curls a superb shot high into the corner past Moore.
Big chance for Chelsea as Azpilicueta floats over a cross towards Bertrand with Moore all at sea in the Brentford goal, but the Chelsea defender cannot get his header on target.
Great chance for Chelsea to draw level as Cahill heads Mata's corner right across the face of goal, but Terry somehow loses his balance and fails to get on the end of the ball. Chelsea keep the pressure on and Ivanovic's acrobatic overhead kick is saved by Moore.
Brentford are starting to get a foothold back in the game now after being stung by Chelsea's equaliser.
Lampard almost gets a free header at the front post from Mata's corner before Brentford clear through Dean.
Chelsea have another chance as Cole gets down the left and cuts the ball back for Mata on the penalty spot, but his effort is saved by Moore.
GOAL: Chelsea draw level with a fine solo effort from Oscar and he controls the ball on the edge of the box, beats two Brentford challenges before poking his effort high into the net past Moore.
Diagouraga almost sends Donaldson in on goal, but Turnbull is quickly off his line to clear the danger.
Moore collect's Mata's free-kick wide on the right at the second attempt to ease the pressure on Brentford.
Lampard's low effort is poor and the ball breaks to Oscar on the edge of the box, but his effort is blocked by a number of bodies inside the box.
Chance for Chelsea as Torres wins a free-kick on the edge of the box. Lampard looks to be the man for this.
Cole gets down the left and pulls the back for Lampard, who sees his scuffed shot blocked by the Brentford defence.
Bob Jackson in Cyrpus believes Brentford deserve their half-time lead and he is struggling to see how Chelsea will come back.
Richard Shirran has been shocked by Chelsea's lacklustre display and believes Demba Ba needs to come on up front to play two strikers up top.
Chelsea fan David Clark in Sydney Australia says as a proud Chelsea fan for 50+ years, I'd accept defeat against Brentford if Benitez would pack his bags and go! What do you think?
If you a fancy a bet on the outcome of the game here are the latest odds from SkyBet. Can the Bees hold on? We have cut them from 9/1 to 2/1 to progress and 7/4 to earn a replay, while Chelsea are 6/4 for a comeback win.
What does either manager need to do at the break? I look forward to hearing from you and I will endeavour to post as many of your thoughts, opinions and reaction as I can.
HALF-TIME: Brentford go into the break deservedly 1-0 in front thanks to the goal from Marcello Trotta just before the break. Chelsea have been poor all half and Simon Moore in the Brentford goal has not been tested.
Free-kick in a promising position for Brentford now. Forshaw plays the ball in low and the ball drops to Forrester and the danger is finally snuffed out. Chelsea look all at sea at the moment.
GOAL: Brentford take the lead as Turnbull keeps out Forrester's superb curling effort from the edge of the box and Trotta is on hand to smash home the rebound. The upset is on.
Turnbull kicks another clearance straight out of play and he has been struggling with his kicking today
Forshaw drills in a shot from the edge of the box which is spilled by Turnbull before being picked up by the keeper at the second attempt.
Torres tries to send Marin clear on goal, but his pass is terrible and it goes straight through to Moore.
Diagouraga is given a ticking off by the referee for a late tackle on Ramires, but he escapes a booking.
Shocking pass from Cahill straight out of play just as Chelsea were beginning to exert a bit of pressure on the home side.
Another chance for Brentford as Forrester bursts through the middle only to drag his effort off target.
Brentford go close as Logan gets in down the left and cuts the ball for Forshaw who curls his shot just wide of the target. The home side are on top here
Lampard with a free-kick for Chelsea with the big boys in the box, but his cross is poor and cleared by Brentford. Probably sums up Chelsea's performance so far.
Great play from Forrester as he slides in to win the ball before skipping past Ramires and firing in a shot from the edge of the box just wide of the target.
Forrester is looking lively for Brentford and most of the home side's attack are coming down his wing as Brentford win their first corner.
The ball is teed up to Forrester from the free-kick, but under pressure the Brentford winger blazes his effort well over the top. Wasted chance for the home side.
Big chance for Brentford as Terry is penalised for a backpass to Turnbull so it will be a free-kick inside the box for the home side.
Trotta has Brentford's first shot of the game, but he slices his shot well wide of the target, but encouraging from the home side.
Good pressure from Douglas on Turbull sees the Chelsea kick the ball straight out of play. Douglas wins a great cheer from the home fans.
Brentford seem content to let Chelsea have hold of the ball as the visitors look to break down the home side.
Oscar has a sight of goal on the edge of the box after picking up a pass from Marin, but he drags his shot off the target.
Chance for Chelsea as Cole gets down the left and fires over a cross right across the face of goal, but Torres can't get on the end of it and the opportunity goes abegging.
Early scare for Brentford as Torres wins a flick on from Ivanovic's long throw, but no one is on the end of it to have a shot at goal.
Ryan on Twitter is predicting a tight game with Chelsea coming out on top 1-0 with Fernando Torres netting the winner.
Jamie Sadler via Twitter is going for a 3-0 win for Chelsea with Oscar, Marin and Torres scoring for Chelsea
Chelsea are the overwhelming favourites at 1/4 with Brentford 9/1 to win and 5/1 to earn a replay. Fernando Torres starts and is 100/30 to score first, while Clayton Donaldson represents the Bees' best chance of netting at 7/2 anytime.
I look forward to hearing from you and I will endeavour to post as many of your thoughts, opinions and reaction as I can.
If you would like to get in contact at any point this afternoon then please don't hesitate. You can mail me via the Score Centre, email me direct on peter.o'rourke @bskyb.com and you can also now Tweet me: @skysportspeteo.
John Terry started his first game for two and a half months in Chelsea's FA Cup fourth-round tie at BrentfordThe fit-again Blues captain made his first full appearance under interim manager Rafa Benitez, who rested goalkeeper Petr Cech and recalled Fernando Torres, Marko Marin and Ryan Bertrand.Eden Hazard's ballboy ban was not the only suspension for today's fixture, with Brentford defender Jake Bidwell joining him on the sidelines for the home side, who also made four changes by drafting in Toumani Diagouraga, Harry Forrester, Shaluem Logan and Marcello Trotta.
Chelsea XI: Turnbull, Ivanovic, Cahill, Terry, Cole, Ramires, Lampard, Marin, Oscar, Bertrand and Torres
Brentford XI: Moore,Logan, Dean, Craig, Hodgson, Douglas, Diagouraga, Donaldson, Forshaw, Forrester, Trott.