Graeme Souness hailed what he described as the "greatest night in Chelsea's history" after the Stamford Bridge club qualified for the Champions League final.
The Blues survived having John Terry sent off and a Lionel Messi penalty to draw 2-2 on the night and go through 3-2 on aggregate.
Sergio Busquets and Andres Iniesta netted for the home side but Chelsea scored through Ramires and Fernando Torres to secure a place in the final.
Souness said: "I think this is the greatest night in Chelsea's history.
"It's remarkable. They showed tremendous resilience.
"You can only get a result out there if you've got total togetherness.
"It's the most remarkable game, I think, I've ever seen.
"There was something about Chelsea tonight where there was a dogged determination."
Former Chelsea manager Glenn Hoddle paid tribute to the performance of goalkeeper Petr Cech who kept Barcelona at bay, fingertipping a shot from Lionel Messi on to the post in the second half.
He said: "He had an absolute stormer Cech, even the one from Messi which hit the post he got a fingertip to it.
"It was an amazing night of football, incredible."
Jamie Redknapp admitted he thought Chelsea had little chance of making the final.
He said: "I didn't give them a chance at half-time. I didn't see there was any way they would keep a clean sheet.
"It was monumental, the collective spirit they have shown."