Andy Murray knows he will have to step up his game considerably when he faces Argentina's Jose Acasuso in the second round of the French Open on Wednesday.

The Brit needed five sets to beat 17-year-old French wildcard Jonathan Eysseric on Sunday and now faces a far more experienced opponent.

Acasuso has a big serve and forehand and is at his best on clay.

"I'll have to play much better," said Murray. "But in terms of clay it would be a very good win."

Murray, who is recovering from a throat infection, has yet to feel totally comfortable on the surface.

That showed as he struggled to put away the novice Eysseric in the first round.

But the Scot does have the experience of making the semi-finals of the juniors at Roland Garros and was based in Barcelona from the age of 15.

"I beat some good players in the juniors here," said Murray.

"Obviously I didn't play on any of the big courts. I don't know how I did in the juniors will have any effect on how I play later in the tournament but I've got a tough match and I've obviously got to get myself in good shape for that one.

"My style of play sometimes isn't great on clay. He's (Acasuso) a very good clay-court player.

"He's had a very good run on the South American clay-court stretch this year. It's a tough match. I have to play much better if I want to win."

Before the tournament, Murray said his target was to reach the fourth round and the second week but beating 25-year-old Acasuso would be a significant achievement along the way.

"I've beaten some great players," said Murray. "Acasuso is not a great player, he's a very good player on clay. It would be a good win.

"I don't think you can start comparing wins like beating Andy Roddick at Wimbledon in straight sets and beating Roger Federer a couple of times and guys like (Nikolay) Davydenko three or four times.

"They're obviously better players and better wins for me. But in terms of clay it would be a very good win, that's for sure."

Murray v Acasuso is scheduled for the fourth and final match of the day on Court Three on Wednesday.