Chelsea face the biggest test of their season on Wednesday when they host Barca in the first leg of their semi-final clash.
The game brings back memories for most Chelsea fans of the controversial 2009 clash at the same stage in the competition when they were denied up to four plausible penalties before Andres Iniesta scored a 93rd minute away goal to seal the Spaniards' passage to the final.
All the coverage prior to the clash between Chelsea and Barcelona
Fabregas returned to the Nou Camp last summer after an eight-year spell at the Emirates Stadium, where he enjoyed a simmering rivalry with the Blues as both teams fought for supremacy in the capital.
Fabregas was involved in a fracas with Frank Lampard in the 2007 Carling Cup final - which Arsenal lost - and he admits he took great pleasure from watching the west London rivals exit the Champions League to his hometown club three years ago.
"The previous night we'd lost the semi-final with Arsenal at Manchester United so I was still a bit upset," Fabregas recalled.
"But I was at home with my family that night. We were about to play PlayStation (believing Chelsea were going through) and then that goal (by Iniesta) was scored.
"It was really happy memories because my whole family are Barcelona supporters."
Many had predicted that with the likes of Xavi and Sergio Busquets already well established in the Barcelona side, Fabregas would struggle to get much game time with the five-time European champions, but the 24-year-old has played 25 of the club's 33 Primera Division games, scoring nine goals.
The midfielder says he has matured in to a much better player since his return to Catalonia, and even claims he may have been tactically naive during his time in the Barclays Premier League.
"I've learned a lot tactically, personally," he said.
"I know my position on the pitch a lot more. Before I was free to do whatever on the pitch at Arsenal, and I wasn't tactically good.
"I was playing wherever I wanted, up and down. Here I have to work much more for the team, individually, and think about the team tactically."
Despite spending eight years at Arsenal, Fabregas only managed to win one piece of silverware - the 2005 FA Cup.
With Barca, however, he has the chance to create history in his first campaign back at the Nou Camp.
Pep Guardiola's men are favourites to become the first team in history to retain the Champions League and Fabregas also has the privilege of being part of a team that contains the likes of Lionel Messi, Xavi and Dani Alves.
"The move has been much better than I expected," Fabregas said.
"I played much more than I expected. I came here to learn, to get better as a player and a person, and also to experience weeks like we start tomorrow [Wednesday].
"We have Chelsea in the semi-finals of the Champions League and then play against Real Madrid in a game which, if we win, we are back in the title race; then against Chelsea again.
"Hopefully we will win all the games and to win the Champions League in my first year at Barcelona would be a dream come true."
Chelsea struggled under Andre Villas-Boas at the start of the campaign but his sacking, and the appointment of interim head coach Roberto Di Matteo, has breathed life in to their season.
Fabregas has been impressed with how the former West Brom boss has fared, claiming his more direct approach has been key to their recent revival.
"What happened with Villas-Boas was they played more from the back," Fabregas added.
"They tried to keep possession and take initiative in the game.
"They've gone back to the type of Chelsea that was more successful a few years ago with Di Matteo: playing on the counter, trying to hit the target man, sitting back and using that number nine as a reference point."