GLASGOW - A Lionel Messi double against Celtic put Barcelona in to the driving seat for the return leg of their Champions League last-16 tie in a fortnight's time.
After surviving a whirlwind start by the visitors, Jan Vennegoor of Hesselink gave the Hoops a 16th-minute lead with a powerful header before Messi levelled two minutes later.
Debutant Barry Robson's looping header just before the end of a pulsating first half gave Celtic an interval lead but, following a mistake by Gary Caldwell seven minutes after the restart, Thierry Henry equalised with a classy finish.
The home side tried valiantly to hang on in the face of a Catalan onslaught but in the 79th minute the Argentina international summoned up another piece of magic inside the Celtic penalty area before curling his shot past Artur Boruc.
The return match on March 4 promises another tough night for the Scottish champions, who will have to win their first ever Champions League game on the road if they are to progress through to the quarter-finals.
On this evidence, it will be a mighty task for Gordon Strachan's men, who suffered their first home defeat in the competition since the last visit of Barcelona in 2004.
With right-back Andreas Hinkel cup-tied and midfielder Scott Brown suspended, Strachan was forced to tinker with his starting line-up.
Teenage defender Paul Caddis was handed a Champions League debut, as was midfielder Robson, who was partnered in the middle of the park by Paul Hartley, with Massimo Donati dropped to the bench.
Frank Rijkaard's problem was an embarrassment of riches and the Barca boss opted to start with a formidable three-pronged attack of Ronaldinho, Henry and Messi.
An open game was all but assured and the first half certainly entertained the capacity Parkhead crowd.
The fluid and inventive visitors took control from the first whistle and only a great save by Boruc from Andreas Iniesta's drive and a headed clearance off the line by Caddis to stop Henry's goal-bound shot kept the Hoops goal intact.
But in the 16th minute, when the home side came up for air for the first time in the match, they took a sensational lead with their first effort on goal.
Aiden McGeady's attempted cross from the left was knocked back out to Lee Naylor but his delivery was powered home by the head of Vennegoor of Hesselink past Victor Valdes from 10 yards out.
Two minutes later, Iniesta and Messi played a one-two inside the Celtic penalty area and despite Naylor's attempted clearance, the ball looped over Boruc and the little Barca striker took the acclaim of his team-mates.
The game looked to have turned in the visitors' favour but there was more drama in the 38th minute when McGeady turned inside Iniesta, lofted the ball in to the Barcelona penalty area and Robson stretched to lift his header over the despairing Valdes from just inside the box.
Stunned Barca began the second half as impressively as they had begun the first but their equaliser in the 52nd minute came only after Celtic defender Gary Caldwell carelessly gave the ball straight to Ronaldinho.
The Brazilian superstar quickly moved it on to Henry on the left-hand side of the penalty area and the Frenchman took a touch before curling the ball past Boruc.
It was one-way traffic. Henry knocked Eric Abidal's cross just past the near post but, as the game took a breather, Donati, on for Hartley, drew a decent save from Valdes with a low drive from 30 yards.
Barcelona should have taken the lead in the 75th minute when substitute Xavi, on for Deco, planted a free-kick right on the head of Gabriel Milito but again Boruc blocked the close-range header.
But in the 79th minute, in yet another Barca attack, Messi got the break of the ball inside the Celtic penalty area, dragged it back on to his left foot and curled a wonderful shot past Boruc.
In the second minute of injury-time, Celtic substitute Georgios Samaras, on for Vennegoor of Hesselink, was booked for diving in the Barca penalty area following a challenge from Yaya Toure.
The Celtic fans protested but, when the final whistle sounded soon after, they gave both sets of players a standing ovation as they left the field.
