MADRID, April 8 (Xinhua) -- FC Barcelona coach Tata Martino believes Leo Messi holds the key to his side qualifying for the semi-finals of the Champions League.
Barcelona travel to play the second leg of their quarter-final tie away to Atletico Madrid on Wednesday, knowing they have to score following a 1-1 draw in the Camp Nou a week ago.
It will be the fifth meeting between the two sides this season and the previous four games have yet to produce a winner with two 0-0 draws and two 1-1 draws.
Martino believes that now is the moment for Messi to swing the balance.
"It's obvious we are used to seeing Leo score in almost every game and when he has played several games against the same rival and has not scored then the tension rises," he said.
"We are interested in him being decisive, but he has many ways of being decisive and he doesn't necessarily need to score a goal to help decide a game. So if we see the best Leo, then our chances are going to increase," added the Barca coach.
Barca won the Spanish Supercup at the start of the season on away goals against Atletico, but failed to score in their league game in the Vicente Calderon stadium.
"I think the two sides know each other very well and the only thing we have not seen in the four previous matches is Barca take the lead -- something that is usually important. If we can do that and manage the game in a different manner," commented the Barca coach.
His opposite number, Diego Simeone maintained the doubt over whether striker, Diego Costa, who only played 30 minutes a week ago because of a muscle injury, would be able to play.
Costa was unable to play in Saturday's win over Villarreal and although he has worked hard in recent days, his fitness is not yet certain
"We will see in the training session, what shape he is in, but if he doesn't play then Adrian (Lopez) will start and I'm sure he'll have a great game."
"You need a player to be at least 90 percent fit, because a half-fit player is no use, whoever they are. Adrian is doing well and I am sure that he will score tomorrow," said Simeone.