Rafael Nadal: Rafa Must Not Underestimate Lukas Lacko in 3rd Round

It's getting to be easier and easier to worry about Rafael Nadal at the outset of a given tournament, as it just seems like he's always battling some nagging injury or another. He's rarely rendered totally unable to play, but he's rarely himself either.

At this point, you honestly have to wonder if Nadal will ever be himself again. He's got a lot of miles on his body. 

But right now, Nadal appears to be just fine. While it's true that it's hard to take your attention off his balky right knee, Nadal has looked rock-solid in his first two matches at the Australian Open, winning both in straight sets.

Given the way he's started, Nadal would seem to be a lock to knock off Lukas Lacko, the No. 119 player in the world, in the third round. In fact, Rafa may even win in straight sets yet again, propelling himself to the fourth round with plenty of energy to spare for the rest of the tournament.

I wouldn't be so sure. While Nadal is certainly heading into his third-round match against Lacko with plenty of momentum, Lacko has some momentum of his own.

It started in the qualifying tournament, where Lacko won all three of his matches in straight sets, dropping a grand total of 11 games. He effectively dominated his way into the Australian Open, and he has refused to go quietly since the start of the tournament.

To boot, Lacko has refused to go quietly against some pretty tough opponents. He battled back to beat 28th-seeded Ivan Ljubicic in five sets, and then he beat Donald Young, No. 42 in the world, in four sets in the second round.

Neither Ljubicic nor Young are anywhere close to being on Nadal's level, but Lacko has proven that he's not going to go down without a fight. If he can hold his own against Nadal and lengthen the match in the process, he might just be able to pull off a monumental upset. For all we rave about Nadal's fitness, you just can't be certain that his body can hold up in a marathon match.

All of this being said, my gut tells me that Nadal will win. I get skeptical of his chances a lot, but he continues to prove that, at the end of the day, he's still Rafa Nadal. On a given day, that means he's unbeatable.

But Nadal is not wholly invincible. If Lacko doesn't remind us of that, somebody else will.

Count on it.