LONDON (Reuters) – The world's best player Lionel Messi lit up the opening night of the Champions League for Barcelona although holders Inter Milan and Manchester United endured less than sparkling starts yesterday.

The Argentine, like last season, treated Europe's blue riband club competition as his personal playground, scoring two classy goals before missing a penalty as Barca recovered from an early shock to thrash visiting Panathinaikos 5-1 in Group D.

Inter took the lead but then had to come from behind to draw 2-2 at Dutch debutants Twente Enschede in Group A with the Italians losing forward Goran Pandev to a knee injury.

The other game in Group A also ended 2-2, Tottenham Hotspur wasting a two-goal lead against Bundesliga side Werder Bremen on their first appearance in the European Cup since 1962.

The impish Messi bagged eight goals in the competition last season and judging by his display at the Nou Camp against an overwhelmed Greek side he will be aiming for double figures again, as Barca set about trying to reclaim the trophy.

Messi would have celebrated a hat-trick but for the second-half penalty save and he also rattled the goal frame before halftime as he resumed normal service after failing to hit the target at the World Cup finals.

David Villa, Pedro and Dani Alves also found the net for the irresistible Catalans who emphatically made up for their shock defeat by promoted Hercules in La Liga at the weekend. "He is the best player in the world by some distance from the rest," said Barca coach Pep Guardiola.

"It hurts him to miss and he has this amateur spirit of always wanting to play."

Inter forward Diego Milito was not far behind fellow Argentine Messi in the Champions League goal charts last season but scored at the wrong end as they began the defence of their crown under new manager Rafael Benitez in jittery fashion.

Milito's own goal briefly left Inter 2-1 behind at Twente after Wesley Sneijder had given the Italians an early lead.

Samuel Eto'o spared his blushes with an equaliser but Inter had to settle for a point after a goalless second half.

"In the first half we deserved nothing. We opened the scoring but after that we faced serious problems," former Liverpool coach Benitez, who faces a colossal task filling the shoes of Jose Mourinho, told reporters.

Turkish side Bursaspor were given a baptism of fire against Valencia, losing 4-0 at home in Group C's other game.

In Group B, Benfica and Olympique Lyon started with victories, neither of them particularly convincing.

Russian champions Rubin Kazan, who stunned Barcelona last season and will face them again later in Group D, were beaten 1-0 at Denmark's FC Copenhagen.

Today marks Mourinho's Champions League bow with his new team Real Madrid hosting Martin Jol's Ajax Amsterdam while last season's runners-up Bayern Munich host AS Roma as the opening games in the competition continue with matches in groups E-H.