Desperation, frustration and finally irritation! That is how a player feels when the going gets tough.
When seeded players fall by the wayside, their anger increases. Not just against themselves, but everyone else in the stadium.
One tends to feel alone in the cauldron, feeling the attention from all viewers from the stands as well as the television channels.
Though one considers a defeat of a seeded player as an upset, it is not necessary the only condition.
Even a defeat of Venus Williams in the second round can be ranked alongside a upset, similar to that of Kim Clijsters.
What else can we expect in the second week of the U.S. Open then? Let us look into the crystal ball.
Laura Robson has already scalped Kim Clijsters and Li Na in this tournament.
Laura can go one step further by defeating the defending champion Sam Stosur in the next round.
With the kind of pressure that Stosur is facing (as well as not-so-great form in the preceding tournaments), Laura is the favourite to cause an upset once again.
Sam Querrey meets Tomas Berdych in the third round on Saturday.
Playing in front of his home crowd should be motivation enough for Sam to upset the sixth-ranked Berdych.
If he does that, it will continue a tradition of Americans who have done well on their home Grand Slam.
The Bryan brothers have achieved almost everything in their partnership, winning all in sight.
Their odd dip in form has caused their opponents to catch them off-guard and that is what will happen in the second week.
Wawrinka is seeded 18th compared to 14th seed Alexandr Dolgopolov, but he has all the shots to go past the Ukranian.
After coming through a tough five-set match against Darcis in the second round, Wawrinka has nothing to lose against Dolgopolov.
Venus and Serena have been in great form in the doubles tournament throughout this year.
Venus has compensated for her lack of form in the singles tournament by her doubles glory.
But, it looks like they might not continue for too long in this tournament, as they come up against the Russian duo of Petrova and Kirilenko.
Sara Errani reached the final in the French Open earlier this year.
She has all the weapons to oust Angelica Kerber in the latter round when they come face-to-face.
Though Kerber has been solid in her game, Sara has just the right mix to cause an upset win.
Lleyton Hewitt also came through a tough five-set match against Greg Muller in the second round.
Hewitt might be out of the news recently, but he is as keen to make an impact on the tournament as anyone else.
His next match against David Ferrer might see the Australian come out with his A-game to oust the fourth seed.
John versus Janko. This is the pairing expected in round four.
Though they differ by just one spot, we can expect to see the lower-ranked Isner beat the Serb in front of his home crowd.
Tipsarevic has been consistent, but Isner is the type that one does not wish to play on his turf.
Serena Williams is ranked fourth while Agnieszka Radwanska is seeded second in the tournament.
The numbers will not matter for Serena as she continues her run to the top spot in the WTA rankings.
Serena will in fact maker her march all the way to the pinnacle this year.
Andy Roddick has announced his retirement after this tournament which means that he will be determined to bow out in style.
With this attitude, Roddick will be looking past the next round against Italian Fabio Fognini to the match against Juan Martin Del Potro.
Though Del Potro has won the title at Flushing Meadows, Roddick will be eager to show him that it was he who won it earlier.
From the performance of Roddick in the early rounds, it is very clear that his game has increased a notch and that is just the right form he needs to beat Del Potro.