Peterborough United are out of the Emirates FA Cup, but the players can hold their heads high after a committed performance at Stamford Bridge and a goal from Tom Nichols was just reward for the 6,000 supporters who were excellent in their support.
Ultimately the class from the Premier League leaders showed as two goals from Pedro, Willian and Batshuayi wrapped up a 4-1 victory with John Terry red carded midway through the second half for a foul on Lee Angol.
Goalkeeper Luke McGee somehow kept out a corner from Willian on four minutes after the ball had rebounded off the base of the near post as Chelsea started brightly.
Moments later, Marcus Maddison swung a dangerous ball into the box, Angol made contact but Begovic was able to keep it out.
McGee produced a fine stop to deny captain John Terry on nine minutes after a low corner to the penalty spot.
Tafazolli headed wide from a Maddison corner after Cahill had pinched the ball from Nichol's toe on the edge of the box.
Loftus-Cheek fired wide on 15 minutes after cutting inside onto his right-foot. The deadlock was broken on 15 minutes, Spanish international PEDRO cutting inside and finding the corner with a fine finish after Posh were caught on the counter attack.
Forrester was cautioned for a foul on Fabregas on 22 minutes. Fabregas himself was booked moments later for a lunge on Nichols.
Batshuayi was denied by McGee on the half hour mark after a fine turn from Willian. Pedro somehow hit the bar from close-range on 32 minutes after McGee had denied Loftus-Cheek who had then squared the ball into the path of the Spaniard.
McGee denied Willian on 39 minutes as Chelsea pressed for a second goal. The home side got that second goal on 43 minutes as Posh were caught on the break, Loftus-Cheek cushioning a pass into the path of BATSHUAYI who fired low past McGee.
Loftus-Cheek side-footed wide of the target after he was played through on goal following an error by Da Silva Lopes. Chelsea made it 3-0 on 52 minutes, WILLIAN curling the ball into the bottom corner from 20-yards.
Bostwick saw a free-kick hit the wall before Nichols saw a shot deflect behind for a corner kick. Chelsea were reduced to 10-men on 66 minutes as John Terry was sent off for bringing down Angol as he raced clear.
Taylor took the free-kick, but his low effort was gathered well by Begovic. On 70 minutes, Posh got a goal back their play deserved, Smith with a low centre, Angol sliced his effort but there was Tom NICHOLS to convert from close-range to send the Posh fans wild behind the goal.
Kante replaced Willian on 72 minutes as Chelsea made another switch with Posh having a right good go at this. The home side grabbed a fourth goal on 76 minutes as PEDRO fired into the bottom corner from the edge of the box.
Posh made their final change on 80 minutes, Jerome Binnom-Williams replacing Hughes. Angol fired over on 83 minutes after a raking pass from Smith.
Chelsea: Begovic, Zouma, Terry (c), Cahill (sub Aina 56min), Ivanovic, Fabregas, Chalobah, Loftus-Cheek (sub Azpilicueta 69min), Pedro, Batshuayi, Willian (sub Kante 71min). Unused subs: Eduardo,, Aina, Kante, Moses, Hazard, Diego Costa.
Posh: McGee, Smith, Hughes (sub Binnom-Williams 80min), Tafazolli, Bostwick, Forrester, Da Silva Lopes, Maddison (sub Taylor 56min), Edwards (sub Samuselon 56min), Nichols, Angol. Unused subs: Tyler, Ball, Chettle, Inman.
Half-time: Chelsea 2-0 Peterborough United
Full-time: Chelsea 4-1 Peterborough United