FC Barcelona failed to turn their first-half superiority into triumph at home against Celtic FC on Matchday 5 as Martin O'Neill's side went out of the UEFA Champions League with their heads held high.
 Celtic had started with all the organisation and confidence which you expect from an O'Neill-trained side. With both Dianbobo Balde and Didier Agathe fit, the Celtic manager was effectively at full strength but chose to leave out creative players like Juninho Paulista, Henri Camara and Aiden McGeady in order to attempt containing the home side in a 4-4-2 formation.
 It had seemed that the idea would work, and frustrate Barcelona, until a series of chaotic events in Celtic's penalty box indicated that the first goal was due to arrive. First, Jackie McNamara almost sliced a clearance past his own goalkeeper Magnus Hedman and then the Swede was forced into a number of desperate clearances away from his own goalmouth.
 Then Barcelona struck. Eto'o drifted deep to pick up the ball and, crucially, was allowed to turn and run at Celtic's defence before playing a wonderfully executed one-two with Deco and poking the ball past Hedman. It was all the encouragement the crowd and Eto'o needed.
 Celtic were already having trouble retaining possession and the home team repeatedly surged up both flanks in search of the second goal. Moments after the first one Sylvinho, the first of Barça's ligament-damaged players to return to duty, received a clever back-heel from Ronaldinho and crossed for Eto'o to slide a volley just past the post.
 The crescendo of noise was rising and so was the tempo of the game – both factors suiting Barcelona immensely. However they spurned the chance to wrap the game up ten minutes before half-time when Ronaldinho's clever pass sent Ludovic Giuly into a one-on-one situation with Hedman. The keeper saved bravely at the Frenchman's feet but Xavi Hernández, following up, sliced the ball over the gaping net.
 Barça poured forward again and after Ronaldinho feinted in one direction and sent Stanislav Varga in the other before feeding Eto'o, the Cameroon international created space and looked certain to score from five metres out but Hedman arrived with perfect timing to save with his outstretched feet.
 Celtic quickly received their reward for such determined and brave defending. Varga inserted himself in front of Carles Puyol to flick Stilian Petrov's 45th-minute free-kick to the back post where Hartson, ruled onside, delicately touched the ball past Víctor Valdés for a half-time scoreline which barely reflected the play, possession or chances.
 Barça's football never dropped to a poor standard yet the confidence which Hartson's goal gave Celtic was evident and influential. By watching the visitors' performance it was hard to understand how the Scottish champions had never so much as drawn an away game in the Champions League.
 Barcelona created fewer and fewer clear-cut chances and as Celtic held the ball and passed it more accurately than at any stage in the first half, the noise from their 10,000 travelling fans became intense.
 So confident was O'Neill that his team might turn improbable equality into incredible victory that he took off centre-half Varga, replaced him with striker Camara and attempted to play 4-3-3 when in possession, but a winning goal proved elusive.