John Hartson joined us to look back at his favourite Champions League memories, including a pair of memorable matches against Ronaldinho's Barcelona in 2004-05.

That Barca side would eventually go out to Jose Mourinho's Chelsea side, but they would prove memorable opponents to Hartson for Henrik Larsson's return to Celtic and Ronaldinho being subdued in the away leg.

Memories turned first of all to Celtic's 3-1 home defeat in the group stage.

Barcelona's Ronaldinho flicks the ball up as Celtic's Alan Thompson (2nd l) celebrates scoring the winning goal

"I remember that game very well, he scored the third goal and I think he lobbed the goalkeeper from a bad backpass. I had come off and I think that Chris Sutton had equalised, if I'm not mistaken.

"Immediately, everyone was looking at Henrik wondering what type of reaction we would get because he was such an icon at Celtic with the goals and everything else. He was an unbelievable player.

"He just walked back to the half-way line as if nothing had happened. He didn't celebrate at all - he hardly mustered a smile - because he had such affection for Celtic and for the crowd at that time."

Ronaldinho subdued

Barcelona's Ronaldinho sits dejected as his side lose against Celtic

Attention turned to the leg at the Camp Nou, where Celtic managed to get a highly creditable draw with a Barcelona side littered with star names - no name bigger than Ronaldinho.

But Hartson remembered that the Brazilian had a quiet time of it thanks to one of Celtic's unsung heroes in Belgian Joos Valgaeren.

"He was right up there [as one of the world's best in 2004]," says Hartson.

"He was an unbelievable talent - quick, powerful, a goalscorer and could make goals. People used to love watching him play, he could turn really sharply. Just a genius on the ball.

"But I have got to say, not many people know this, but Martin O'Neill had earmarked Joos Valgaeren to man-mark Ronaldinho. Ronaldinho didn't get a kick!

"Martin said to him 'listen, if he goes to the toilet, you have to follow him in!'

"He probably produced one or two little bits but not enough to influence the game, and that was mainly due to the Belgian centre-half.

"He did a fantastic job that night, I have to say."

John Hartson was talking to OTB as part of our Champions League Best Moment series, in association with Virgin Media Sport  #WeFreeSport.

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