US Open Tennis 2013: Recapping Day 1's Biggest Surprises

Top-seeded favorites like Rafael Nadal and Serena Williams had very little trouble advancing to the second round on Day 1 at the 2013 U.S. Open, but that doesn't mean the tournament's opening action didn't feature a few notable upsets. 

Two-time U.S. Open champion Venus Williams looked awfully impressive in her stunning straight-sets win over Kirsten Flipkens at Arthur Ashe Stadium, while Great Britain's scorching-hot Daniel Evans sent Japan's top-ranked player packing after just three sets.

Here we'll recap the biggest surprises from Day 1 at Flushing Meadows.

Andreas Haider-Maurer Knocks Out Ernests Gulbis (30)

Despite dropping the first set 3-6, 88th-ranked men's singles player Andreas Haider-Maurer battled back against Ernests Gulbis, winning the second set and then fending off the Latvian in a hard fought fourth-set tiebreak to force a fifth and deciding frame.

After earning a key break in the final set, Austria's Haider-Maurer would close out the set and the match 6-4 to book a trip to the second round in Queens.

Gulbis, who had victories over Andy Murray and Jo-Wilfried Tsonga in 2013, was viewed by many as a potential dark horse to reach the semifinals from David Ferrer's quarter of the draw. 

The New York Times' Ben Rothenberg discussed Gulbis' disappointing loss, adding that the 24-year-old had looked excellent in training in lead-up to the tournament. But, according to Gulbis, nerves got in the way, per Rothenberg:

"

When I came into the match, maybe I got over nervous. Because today in the morning, I woke up and I felt tight. I felt nervous in the warm-up and in the morning I felt tight, couldn’t relax. And when you’re so tight you lose a lot of energy on court. So after two sets I was already exhausted. I was sweating more than usual, everything was — I just tight, I was uptight.

"

Haider-Maurer will advance to play Mikhail Kukushkin in the second round.

Venus Williams Dominates Kirsten Flipkens (12)

Belgium's Kirsten Flipkens reached the semifinals at Wimbledon earlier this summer in her most recent Grand Slam appearance, but that didn't matter to unseeded Venus Williams, who jumped on the No. 12 seed's lackluster serve early on, winning in straight sets and dropping just three games in all.

The performance, highlighted by Williams' magnificent return play (61 percent receiving points won), was one of the more dominant outings the 33-year-old has had since being diagnosed with Sjögren's syndrome (an autoimmune disease) two years ago.

After the victory, Williams was quick to point out her struggles over the past two years and the positives she's taken away from past defeats, per The Washington Post:

"

For me, I stay positive because I know I can play great tennis. Sometimes you just have to go through more than what you want to go through. Sometimes you have to have losses. When I had losses, it always motivates me a lot to do better and to work harder.

"

Williams will have to capitalize on her service opportunities more often moving forward in the women's draw. If she continues to hit her forehand with the same amount of pop that she was against Flipkens, she'll be a difficult out for any of the top contenders.

Daniel Evans Takes Out Kei Nishikori (11) in Straight Sets

Great Britain's Daniel Evans pulled off the biggest upset of Day 1 by far when he knocked off 11th-seeded Kei Nishikori in their first-round matchup on Court 13, defeating him comfortably in straight sets.

Evans, who is ranked No. 179 in the world, had to win three qualifying matches last week just to earn a spot in his first-ever U.S. Open main draw. Meanwhile, Nishikori reached the third round in Flushing Meadows a year ago and made a quarterfinal appearance at the Australian Open in 2012.

But Evans, who had never been past the first round at a major prior to Monday, isn't satisfied just yet, according to The Guardian's Kevin Mitchell:

"

Winning one is not enough. I want to win the next few matches as well. I've been playing really well for five weeks now.

"

Evans will be a mighty underdog again in the second round against Bernard Tomic, but if he can continue to win a high percentage of first-serve points and convert points at the net, he'll have a shot to keep his dream run alive against the unseeded Aussie. 

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