Frank Lampard opened the scoring at the 16th minute but Jason Roberts cancelled it at the 63rd minute and the Blues had to wait for a 109th minute killer from Ballack to go through.

The German skipper gave Lampard an excellent pass in the area before the England international dribbled past his marker and slotted into the back of the net.

Chelsea dominated the first half and produced the best of chances as Joe Cole lost an easy chance of a well placed chest pass from Didier Drogba, Cole's effort was denied by goalie Brad Friedel and Drogba puts an awful pass that was intercepted by Dunn instead of Andriy Shevchenko who was all alone in front of goal.

The second half, Blackburn had a good reaction as they went upfront and could push the Blues to get back in defense. Although Sheva had a golden opportunity to kill the match as Drogba offered him an easy chance in the area but he lost his balance and lost the ball in a very comic scene.

Petr Cech had to make some excellent stretches before he got beaten by Roberts who cleverly deflected in a Morten Gamst Pedersen free kick in the 63rd minute.

Once again Chelsea got back to action in an attempt to get the winner before extra-time and Jose Mourinho brought in Salomon Kalou, Shaun Wright Philips and Jon Obi Mikel to boost his goal chances, in vain.

Philips made the Portuguese coach proud of him as he dribbled in the area and passed it to Kalou who lost the ball to find Ballack’s powerful shot and put his team back in the lead.

The victory keeps Chelsea on course for an unprecedented quadruple of trophies.