Chelsea coach Jose Mourinho saluted his side's mental strength after Didier Drogba rescued a 2-2 draw away to holders Barcelona with a last-gap equaliser on Tuesday to leave his side on the verge of reaching the last 16 of the Champions League.
"The performance was brilliant - we played very, very well. Tactically, we were always in control against a very difficult team," said Mourinho after his men made it four points from two games against Barca and ten points from four Group A encounters.
"The team did collectively very well - we were mentally very strong," added Mourinho, who made light of his side's six bookings, including one for midfield dynamo Frank Lampard, who will now miss the trip to Werder Bremen.
The Germans, 3-0 winners in Sofia, stand three points behind the Blues but two points ahead of a Barcelona side they must nonetheless still face at the Nou Camp.
"This group is the most difficult group in the Champions League," insisted Mourinho, who praised Drogba's neat finish deep into injury time after Eidur Gudjohnsen looked to have given Barca victory with a 56th-minute goal against his former club.
"His contribution was magnificent. When he had the big chance he put the ball in the net," said Mourinho of the Ivorian international striker who is now competition top scorer with five goals.
Barca meanwhile must scrap to ensure they stay in contention.
"We generally played very well, we were very close to winning," said coach Frank Rijkaard.
"Chelsea are a strong team. They play hard but they are a very good side. We began well but they came right back at us and began creating chances.
"Now we have no margin left - we must win at Levski Sofia," said the Dutchman, who ended a 14-year wait for what was only Barca's second title win last May at the expense of Chelsea's London neighbours Arsenal.
Mourinho said he would not get carried away with a result which showed Chelsea need fear nobody after making it 13 games without defeat in all competitions.
"Six or seven teams can win the competition," said the man who has already performed the feat as a coach, with unfancied Porto in 2004.
One of his former Porto charges, Deco, scored the opener in the third minute with a sweetly-struck drive which delighted the 95,000 crowd.
On 52 minutes, Lampard, just onside, escaped his marker inside the box to fire the equaliser, clipping home from the acutest of angles.
His suspension will not unduly worry the English Premiership champions after a result which essentially left them cruising towards the next phase.
Barca regained the lead when Ronaldinho came alive on the left to dink a ball low into the Chelsea box, where Gudjohnsen gleefully smashed home from four yards after 57 minutes.
Gudjohnsen had been almost anonymous during the 1-0 reverse a fortnight ago at Stamford Bridge against his former employers but his glory was short-lived as he picked up a booking, then gave way to Ludovic Guily and then saw former sidekick Drogba score the goal which could yet eliminate his new club.