A missed penalty from Cristiano Ronaldo ensured FC Barcelona and Manchester United FC remain deadlocked at 0-0 after an enthralling first leg of their UEFA Champions League semi-final.

Extraordinary scenes
The English side's last visit to the Camp Nou had ended in extraordinary scenes as they won the 1999 UEFA Champions League with two added-time goals, and they almost picked up where they left off on their first return since, only for Ronaldo to fire a third-minute penalty wide after Gabriel Milito had handled. It was as close as they came on a night when Paul Scholes made his 100th appearance in the competition, although the visitors will be thankful to escape with a draw after being forced on the back foot for much of the match.

Penalty miss
The tie sprang to life from kick-off, providing drama as early as the second minute when Ronaldo headed on Scholes' corner only for Milito's raised arm to intervene. The Portuguese international took the spot-kick himself, but fired wide to the relief of the majority in the 98,000 sell-out crowd. Well off the pace in the Primera División, Barça's season rests on this tie and they quickly found their feet, a lightning run from Lionel Messi putting the away team on the back foot. It was breathless stuff as the home side probed a makeshift United back line, shorn of the unwell Nemanja Vidi.

Attacking intent
Sir Alex Ferguson had named an attacking side with Ronaldo, Wayne Rooney and Carlos Tévez all selected, but they could not break out of their half. Starved of possession, Ronaldo reacted angrily as Rio Ferdinand pumped a clearance high over his head and soon after Rooney was forced to clear off the toes of Samuel Eto'o deep inside his own area. Against the run of play, though, United nearly broke through. Andrés Iniesta's misplaced pass let in Ronaldo, who was eased off the ball by Rafael Márquez as he closed in on goal.

Ronaldo chance
Despite Barcelona's possession, United goalkeeper Edwin van der Sar was rarely troubled, a low save from the returning Deco's free-kick on 38 minutes his main contribution of note as half-time approached. At the other end Ronaldo's darting run was halted by Márquez's clumsy challenge, with the resulting booking ruling him out of the second leg.

Classic encounters
The talk in the build-up had been of classic encounters between the sides and the second half began at a pace worthy of the fixture. On 48 minutes Messi's shot was blocked, then Michael Carrick's tackle kept out Eto'o. Moments later Eto'o drove into the side-netting before Carrick did likewise at the other end. United breathed a sigh of relief when Bojan Krki replaced the tiring Messi two minutes past the hour.

Evenly poised
The home team could still not find a way through, with Van der Sar forced to push away Thierry Henry's fierce drive after the Barcelona substitute had cut inside from the left, and United looked increasingly dangerous on the break as the half progressed. Neither side, however, could break the deadlock, leaving the tie evenly poised for the return at Old Trafford next Tuesday.