Fernando Torres' controversial late strike helped Chelsea to claim a 4-2 victory over a spirited Reading side at Stamford Bridge.
The result had been cruel on Reading, who had led 2-1 at the break, especially as Torres was clearly in an offside position as he tapped home a cross to give the home side the lead with just 9 minutes remaining.
After Frank Lampard had given Chelsea an early advantage from the penalty spot, Reading showed plenty of attacking endeavor to storm into the lead with goals from Pavel Pogrebnyak and Danny Guthrie. A second-half strike from Gary Cahill brought Chelsea level, before Torres' strike and an injury time striker by Branislav Ivanovic gave the scoreline a flattering edge.
While the match will be remembered for Torres' goal, the other story was a costly goalkeeping error apiece from Chelsea's Petr Cech and Reading's Adam Federici. Although Reading will be bitterly disappointed to go home empty handed, they can take plenty of solace from an encouraging performance against a much-vaunted Chelsea side.
Eden Hazard had grabbed many of the pre-match headlines having played a part in both goals against Wigan and the Belgian looked to carry on that form as he fired wide across goal in the opening two minutes.
In similar manner to how he won the penalty on Sunday, Hazard's close control led to another opportunity from the spot after 18 minutes. The attacking midfielder twisted and turned Chris Gunter before the right back felled Hazard with a clumsy tackle that left referee Lee Mason with little option but to point to the spot.
Frank Lampard stepped forward and slammed home the penalty in customary fashion low to goalkeeper Adam Federici's right.
The goal had been just reward for a bright beginning from the Champions League winners, but to their immense credit Reading far from wilted under the pressure.
The newly promoted side looked to the force their way back into the match and did so just seven minutes later.
Pogrebnyak produced a stunning header from all of 14 yards out after Reading displayed some fine one-touch link up play down the right to work a crossing opportunity for Gareth McCleary.
But while that strike was all about a fine finish from the Russian, Reading's second owed everything to a true goalkeeping blunder.
Guthrie struck low and hard around the wall, but Cech diving to his left for what should have been a simple save, let the ball embarrassingly bounce straight off him and into the back of the net. The keeper's less than fond memories of Reading continuing after the fractured skull he suffered against the Berkshire outfit back in 2006.
Things could have gotten even worse for Cech and Chelsea late in the opening period. Veteran Ian Harte showed he has lost none of his abilities from set pieces with a fine in-swinging free-kick that found Alex Pearce completely free behind the Chelsea back line, but the midfielder somehow just failed to get his head on the ball.
Chelsea almost produced an immediate response as they too went close with the first-half expiring. Hazard, with time to pick out a cross from the right, found Torres perfectly in between two defenders but the Spaniard sent his header disappointingly wide back across goal.
Stamford Bridge was left stunned at the break and Chelsea did little to engineer confidence with a less than inspiring beginning to the second half.
Di Matteo decided to bring on Oscar after 57 minutes and the silky Brazilian quickly looked to get involved as he struck a low effort on target but too close to Federici from 20 yards.
With the match moving inside the final 30 minutes, Chelsea were beginning to put Reading under some pressure. The first real threat after the break came as Torres' cross to Branislav Ivanovic was well thwarted before a Hazard drive was well blocked by some resolute defending.
All that good work was undone, though, by the second goalkeeping mishap of the night.
Hazard laid the ball square to Cahill coming forward from the back and from all of 30 yards the England defender let fly with a decent effort, but one that should have been comfortable for Federici. In almost identical fashion to Cech, though, the Australian could only parry the ball into the back of the net. For Federici the disappointment was only heightened after a similar blunder cost his side a goal in the 1-1 draw with Stoke on Saturday.
If that had been a cruel blow, things were about to get even worse for Brian McDermott's side. As the match entered its 80th minute, some impressive Chelsea interplay on the edge of the box saw Ashley Cole found in space down the left and the tricky midfielder crossed low for the Spaniard to side-foot home from close range. The initial hesitation in Torres' celebration spoke volumes as replays clearly confirmed that he was in an offside position.
As Reading poured forward late on to try and make another comeback, Chelsea struck once more to secure the three points. With Federici upfield, Chelsea broke at pace and Hazard laid in Ivanovic to produce a simple finish into a virtually unguarded net.