Ana Ivanovic's poor run of form in 2016 continues despite a bright start in the opening set in her first round match with the Czech Republic's Denisa Allertová on the Louis Armstrong Stadium at the US Open.
However, the 29th-seeded Serb struggled with her serve, and her forehand eventually let her down in key moments in this encounter.
Allertová starts slow
In the opening game of the match, the world number 90 found herself under pressure with Ivanovic breaking her serve, with three winners, handing Ivanovic the game to 15 due to a backhand unforced error.
However, errors were flowing from both players racquets, seeming to be a comfortable service game for the former world number one at 30-0 but committed unforced errors, however, she strung two consecutive points with a service winner out wide and a passing shot to consolidate the break at 2-0.
Allertová's second service game seemed to be a straightforward one at 40-0 but a forehand unforced error, Ivanovic followed up with a forehand return winner on the Czech's serve and applied more pressure with the game at 40-30 by missing a simple put away, as Allertová was distracted by Ivanovic's movement and placed a forehand into the net.
Fortunately, she was able to get on the scoreboard at 2-1 with the help of Ivanovic committing errors.
The following game, Allertová had three opportunities to get the immediate break back, however, the 2008 French Open champion was able to find a crosscourt winner and put in good serves when she needed them to consolidate the break at 3-1 in a game that lasted over seven minutes.
The next two games were comfortable holds for both players and in the seventh game, Allertová held to love by producing a forehand cross-court winner and clinched the game from a failed drop shot attempt by Ivanovic, despite being a break down at 4-3, she was trying to find a break back.
Ivanovic found herself at 0-30 on serve, and both players were exchanging in baseline rallies, however, the 29th seed's one-two combination of a serve out wide, and a forehand winner, followed by another service winner ensure Ivanovic's lead at 5-3.
Allertová had the task of serving to stay in the opening set but trailed at 0-30 with Ivanovic constructing a blistering forehand return, and a forehand winner into the court with good footwork.
It seemed as though, the 29th seed was going to clinch the set but four consecutive errors handed Allertová a lifeline and made Ivanovic serve out the opening set.
Ivanovic fails to serve out the opening set
The former world number one had a horror game with uncharacteristic errors spewing out of nowhere, a double fault and a forehand forced error drew Allertová level at 5-5.
However, the Serb put that disappointment behind her by immediately breaking back with a backhand winner on the line to create three more break points, and a wild forehand unforced error going out of the court gifted Ivanovic the break at 6-5.
It was deja vu for Ivanovic, as she was struggling to wrap up this opening set by starting the game with a fourth double fault in the match, and a thunderous return winner by the former world number 55 on Ivanovic's second serve to build a 0-30 lead.
The 2012 US Open quarterfinalist was able to find her serve drawing more forced forehand errors from the Czech's racquet, and a first set point chance arrived with a backhand unforced error, however, Allertová saved it with Ivanovic's forehand going wild.
More errors from Ivanovic allowed Allertová to break back and take the opening set to a tiebreak.
Allertová clinches the first set in a tiebreak
The first three points of the tiebreak had unforced errors with Ivanovic initially having the mini-break advantage, and the Czech led 3-2 with an unreturnable second serve, and a wayward forehand going long from the Serb.
Under pressure, Ivanovic's footwork was on point by coming to the net, producing a backhand volley winner to have the tiebreak tied at 3-3 before the change of ends.
Allertová gained the mini-break advantage, and consolidated the lead at 5-3 from the Serb becoming erratic, and produced another backhand forced error.
However, Ivanovic regained the minibreak with an exquisite running forehand crosscourt, drawing the error from Allertová but the Czech was able to clinch the opening set with two lackluster unforced errors from her opponent to take it seven points to four in the tiebreak in 53 minutes.
The Czech runs away with the match
At the conclusion of the opening set on the Louis Armstrong Stadium, Allertová went off court for a comfort break, however, upon her return to the court, she carried on where she left off by breaking Ivanovic's serve with a punishing second serve return to create the second break point opportunity, and Ivanovic's forehand went long to hand the Czech the break.
The world number 90 consolidated the break with ease, secured by a backhand winner.
Ivanovic responded with a love game but was trailing 2-1 in the second set, and a set down.
From then on it was one-way traffic for Allertová, as Ivanovic was trying to go for her shots on the baseline, but forehands and backhands continued to miss, going into the net and just missed the edge of the line, and it was an easy hold for Allertová to consolidate the break at 3-1.
Allertová's forehand cross-court winner brought up three more break points for the insurance break, and she got the insurance break gifted to her as Ivanovic served a double fault.
The Louis Armstrong Stadium was subdued and couldn't believe what they were witnessing, but a crucial challenge from Allertová in the sixth game would have brought up three break points for Ivanovic to retrieve one of the break backs, but Ivanovic's shot just missed the back of the baseline, and Allertová secured the game with the Serb's backhand sailing into the net to lead 5-1.
The recently-married Ivanovic had game points to salvage the match, and forced Allertová to serve out the match but Ivanovic's good first serve, and missed attempt at a backhand crosscourt winner let her down, and another double fault brought up a first match point for the Czech.
Allertová was able to clinch the match point at the first time of asking with a ferocious return, Ivanovic placed on the baseline on the backfoot committed a backhand forced error into the net.
Allertová deservedly clinched the match 7-6 (4), 6-1 in 1 hour and 18 minutes to reach the second round in New York for the second consecutive year.
Match stats
Ivanovic had 17-12 winners but the unforced errors let down the 29th seed by committing an unforgiving 41 to Allertová's 21.
Allertová found more success on her second serve at 68 per cent compared to her first serve at 57.
This was Ivanovic's second consecutive first round exit at a Grand Slam which happened to be the first time since 2011 that she suffered back-to-back first round exits at Slams.
The reward for the Czech is a second round meeting with Karin Knapp or Johanna Larsson.