NEW HAVEN, CT, USA - Timea Babos completed a stunning victory in the first round of the Connecticut Open presented by United Technologies on Monday, ousting No.4 seed Kristina Mladenovic in straight sets, 7-5, 7-5.

Mladenovic came into the match holding a 4-2 head-to-head advantage over her friend and former doubles partner, but it was Babos who eclipsed the Frenchwoman, casting another shadow on the World No.14’s rocky summer hardcourt season.

"It's always difficult to play against Kiki, I've known her since we’re eight years old," Babos said in a post-match on-court interview. "You kind of know what to expect, but still it’s not easy, maybe mentally it’s not easy, but I’m just happy I managed it today, and we’ll see what happens later on.”

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Babos had the initial momentum, as she broke an error-prone Mladenovic in the opening game, and served powerfully to consolidate the break at love for a 2-0 lead.  

Mladenovic was able to level the match at 3-3, and the duo traded breaks at 4-4, with the server double faulting down break point both times.  Serving at 5-5, Mladenovic again double faulted down break point, and Babos carefully closed out the set on her second set-point.

Mladenovic was cursed by seven double faults throughout the first set, including one each at the end of all three games in which she was broken. The fourth seed also had only 8\eight winners and a whopping 21 unforced errors in the set.

Babos had 18 unforced errors in the set as well, but counter-balanced those with 12 winners, including some impressive down-the-line backhands to power her through some of the closely-contested games.

As the second set started, it appeared that the match would swiftly go in Babos' favor, as, in a repeat of the first set, Mladenovic dropped her first service game by double-faulting on break point, and Babos held with ease for a 2-0 lead.

But the tide quickly turned when Mladenovic won eight straight points, breaking Babos at love to get back to 2-2, and then closing out a love service game with an ace for a 3-2 lead.  When the Hungarian put a backhand into the net to give Mladenovic a break advantage, a third set seemed imminent.

But Mladenovic could not convert two set-points on her serve at 5-3, and once more double faulted on break point to put the set back on serve.  A third set point, this time on Babos' serve, went unused as well, and the set was knotted at 5-5.

Babos took control from there, taking advantage of two more double faults from Mladenovic to break for 6-5.  An ace set up triple match-point for Babos, and a powerful forehand gave her the upset win.

"I started off really well in the second set, and then I had a little bit of a down moment and she started to play better," Babos stated in her on-court interview.  "I thought it was just a little bit of time and it’s gonna come back, and it did, so I’m happy to get through."

Mladenovic will rue the 12 double-faults - five of which came down break point - and 40 unforced errors that came off of her racquet today, and is still struggling to find her form in the midst of a four-match losing streak.

Conversely, Babos obtained a much-needed victory, clinching only her second win in her last 12 matches.  She advances to the round of 16 in New Haven for the first time in her career, where she will face Australia's Daria Gavrilova, who survived a three-set tussle against Kristyna Pliskova of the Czech Republic.