Chelsea’s hopes of a consolatory Europa League crown hangs in the balance after a testing defeat in Romania.
Lusescu converted the only goal of the game from the penalty spot, after Ryan Bertrand was adjudged to have bundled over Rusescu.
But despite that set-back just after the half-hour mark, Chelsea could not claw back the deficit and snatch a crucial away goal, meaning there is it all to do for the Blues next week.
Yossi Benayoun was given a starting line-up spot with Juan Mata rested, and the Israeli set out to impress behind his former Liverpool team-mate Fernando Torres, who needs to do some impressing of his own.
The latter did indeed present Chelsea with a promising opening, skipping past outstretched legs, and when all the ball needed was a square pass into the box, the Spaniard tangled his legs up and the ball went hilariously out of play for a goal-kick.
It was a quiet game until the penalty incident. Latovlevici was always in front of Ryan Bertrand, and as the youngster tried to claw back some ground, Rusescu stood his ground and the assistant referee saw enough contact to prevent the goal-scoring opportunity.
Lusescu picked up the ball and hammered the ball to Cech’s right, and though the goalkeeper went the right way, the pace of the ball proved too much.
Could Chelsea recover on an unfamiliar ground? Indeed, they had the best part of an hour to score in.
Benayoun nearly restored parity within five minutes. Hazard’s pass to his team-mate was good, the shot good, but the save great as Tatarusanu continued to deny Rafa’s men, before denying Torres just before the half-time whistle blew.
Tanase nearly doubled the Romanian’s advantage shortly after as Chelsea failed to wake up, but were thankful to see his volley go narrowly wide.
Torres continued to be provided with good balls as Lampard found the Spaniard, but when shooting was the more apt option, the ball was passed and the chance evaporated.
Chelsea’s influential man, Juan Mata, needed to come on, but tasked with changing the game around was always going to be tough in the 30 minutes he was afforded.
Hazard, who had been quiet all game, could have scored after neat exchanged between Bertrand, Lampard and Torres, but his shot flew over the bar.
Marko Marin took the Belgian’s place moments later and proved no less threat to Tatarusanu’s goal, firing at his goal.
David Luiz tried his best to score for the Blues with his free-kick as Chelsea picked up the urgency, but it was too little, too late for Chelsea, who fly back to London needing a confident result against Manchester United on Sunday.