UPDATE 2-Soccer-Messi hits double in Barcelona's win at Celtic

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By Kenny MacDonald

GLASGOW, Feb 20 (Reuters) - Argentine striker Lionel Messi hit a double as Barcelona beat Celtic 3-2 in the first leg of their Champions League first knockout round tie at Parkhead on Wednesday.

The Spanish side came back twice from behind to eventually sink Celtic with Messi's winner 11 minutes from the end of a thrilling match that marked their 100th win in the European Cup.

Celtic had led after 16 minutes through Jan Vennegoor of Hesselink before Messi levelled two minutes later. Midfielder Barry Robson put the home side in front again before the break but Thierry Henry pulled one back early in the second half.

"It is disappointing to score two goals at home and to lose 3-2. They have the best squad in the world and only time will tell if they have the best team in the world," Celtic manager Gordon Strachan told a news conference.

"They are probably favourites to win this tournament now and if you went to the bookies tomorrow they would be the favourites."

Barcelona assistant manager Johann Neeskens said his side could have scored more goals.

"We were dominating the game and controlling the game. We showed we could score some more goals," he told reporters. "We are very happy that we had this result against this team which is a very strong team."