PSG will come up against an 'unstoppable' player when Lionel Messi visits the Parc des Princes for Wednesday's Champions League quarter-final, according to manager Laurent Blanc. Barcelona travel to Paris for the first leg and Blanc, who never won the competition as a player, is well aware of the threat posed by the magical Argentine. Messi has been in sensational form since the turn of the year and he now has 45 goals in 44 games - a total he will be hopeful of adding to against the Ligue 1 champions. Barcelona forward Lionel Messi celebrates after scoring against Sevilla in La Liga on Saturday . Messi bends home his side's opening goal at the Estadio Ramon Sanchez Pizjuan during Barca's 2-2 draw . Messi will lead the line for Barcelona when they take on PSG at the Parc des Princes on Wednesday evening . Speaking ahead of Wednesday's game, Blanc said: 'Lionel Messi is unstoppable. If he scores 40 goals, he's had a bad season! 'But we can't just focus on him. The solution must be collective, man marking doesn't work.' The hosts must also be wary of Messi's strike partners Luis Suarez and Neymar during the first leg, particularly with the away goals rule in place. Blanc added: 'We will need to be aggressive defensively but in the good sense of the term, to be able to stop their attackers.' The second leg will be held at the Nou Camp on April 21. PSG manager Laurent Blanc has described Messi as 'unstoppable' as his side prepare to face Barcelona . PSG's players train on Tuesday ahead of their Champions League quarter-final first leg with Barcelona . Blanc (top left) watches on as his players get put through their paces before Wednesday night's game .
PSG face Barcelona in the Champions League quarter-finals on Wednesday .
Laurent Blanc says his side must not just focus on Lionel Messi .
He wants PSG to be 'agressive defensively' to keep out Luis Enrique's side .
The second leg takes place at the Nou Camp on April 21 .
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