Wimbledon 2012: Looking Ahead to the Biggest Matches of Day 4

Rafael Nadal and Maria Sharapova headline the action on Day 4 at this year's Wimbledon, but they aren't the only top-seeded players who'll be competing on Thursday.

It's going to be another full day of tennis on the grass of the All England Club. As these athletes move on from one round to the next, the tests just keep getting tougher.

Let's take a look at the biggest matches of Day 4.

Rafael Nadal (2) vs. Lukas Rosol 

Rafael Nadal was tested in his first-round matchup with Thomaz Bellucci, but he managed to get out of the match in three sets. 

He'll need to stay sharp against Lukas Rosol as this is a potential trap match.

Rosol is currently ranked No. 100 in the world and he's never won a singles title on the ATP. Nadal should have no problems dispatching the Wimbledon first-timer.

Maria Sharapova (1) vs. Tsvetana Pironkova

Maria Sharapova and Tsvetana Pironkova started this match on Wednesday, with Sharapova currently up 7-6, 3-1.

The match was suspended due to poor light, but Sharapova looked far from her best in the first set. She could have easily dropped the first set if not for a late rally.

Sharapova has the advantage now, but she will need to come out stronger in her next match if she is able to close out Pironkova.

Jo-Wilfried Tsonga (5) vs. Guillermo Garcia-Lopez

Jo-Wilfried Tsonga was on fire in Round 1 with his serves, nailing an incredible 21 aces against Lleyton Hewitt. Tsonga was a semifinalist in last year's tournament and he should have no problems with Guillermo Garcia-Lopez, who's never made it out of the third round.

Garcia-Lopez is coming off of a five-set match in his first-round matchup with Edouard Roger-Vasselin, so he'll be hard-pressed to keep up with the fast-paced game that Tsonga plays. It should be over in three sets, but you never know what will happen. 

That's why they play the game.

Serena Williams (6) vs. Melinda Czink

I've picked Serena Williams to win this tournament for the fifth time, so I'm heavily invested in watching her play.

Her opponent shouldn't give her much trouble. Melinda Czink has only won one tournament as a pro and she's never gotten out of the third round at Wimbledon. 

This is a true David vs. Goliath match, but in this case, Goliath is going to win.

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