Jose Acasuso, 45th ranked player from Argentina, can add his name to the list that includes Tomas Berdych and Janko Tipsarevic, men who gave Roger Federer a scare in a major.

Acasuso was effectively trading groundstrokes with Federer, pressuring him off the ground, leaving Federer scrambling much like Andy Murray was scrambling.

A day after Andy Murray dug deep from 5-1 in the third set against Italian, Potito Starace, to win in four tough sets, Federer found himself playing a suprisingly hard hitting Argentinian.

You expect someone like Murray to struggle against lesser opponents. He doesn’t have the power of Federer, nor the heavy ball of Nadal. He doesn’t seem to hit much harder than his opponents. Tight matches are expected. But Federer? Here’s a guy that takes risks, hits low percentage shots. In rallies, he’s often taking advantage of the situation. You don’t often see players attempting to dictate to Federer. And yet here was Jose Acasuso, trading tough groundies (and he had a one-handed backhand!) doing just that. It looked for all the world that Acasuso was going to upset the world number 2, making the hoped for meeting of Nadal vs Federer moot.

Acasuso had a break in the first set and was up in the first set tiebreak, only to lose the tiebreak 10-8. Despite the loss of the first set, Acasuso continued to pressure Roger taking the second set 7-5. Up 4-0 in the third, then 5-1, Acasuso was unable to press a two set advantage. Federer stormed back and forced a tiebreak, which he won easily, 7-2. After that, Acasuso had nothing more to offer, as Federer confidently finished the fourth set, 6-2.

The bad news for Federer was that he struggled in a second match (his first, he won easily, but he didn’t look that sharp). The good news is that he’s looked better as the match goes longer. Normally, against better players, Federer starts off well, then fades at the end.

These kinds of matches separate good players (those ranked 40ish) from great players. When great players are struggling, they still manage to win, and the good players begin to wilt under the pressure. Federer is likely to say that Acasuso played him tough, but he’s not worried, that he is happy with the way he fought back, similar words to those of Andy Murray when he explained his struggles in the second round.

They say tennis is 90% mental. The physical component is certainly important. No one doubts that Federer and Nadal hit shots better than others. But the mental component is just as important. It allows these players to win close matches, and to come back when they are down.

On to the rest of the matches.

Former world number 4, Nikolay Davydenko, has been steadily working his way through the draw. He beat another Argentinian, Diego Junquiera (age: 28, rank: 80), in four sets: 4-6, 6-3, 6-0, 6-2.

In one of the tougher matchups of the second round, Frenchman Jeremy Chardy beat Italian Simone Bolelli, in five sets: 6-2, 6-3, 4-6, 4-6, 6-1.

Spaniard Tommy Robredo continues to roll through the early rounds beating fellow Spaniard, Daniel Gimeno-Traver (age: 23, rank: 114) in straight sets: 6-4, 6-4, 6-3.

Igor Andreev, 25th seed, had a tough five setter against an Argentinian as well. He beat Martin Vassallo Arguello (age: 29, rank: 49): 1-6, 7-5, 5-7, 6-3, 6-4.

Finally, in a match that was expected to give del Potro problems, an easy straight set match instead. del Potro beat Serb, Viktor Troicki (age: 23 rank: 32): 6-3, 7-5, 6-0.