Patricia Maria Tig scored the biggest win of her career, upsetting 16th seed Sloane Stephens 6-2, 6-3 in the second round of Madrid.

Tig grabs break immediately, never looks back to cruise to first set win

Stephens has had a brilliant start to 2016, winning titles in Auckland, Acapulco and most recently on the clay of CharlestonHowever, she looked lethargic, slow-footed and disinterested in this match and Tig made her breakthrough right away, breaking the American's serve to start the match, a deft drop shot getting the job done.

The Romanian doesn't have a particularly strong serve, but she only lost four points on it in the opening set. Unable to make an impression and visibly frustrated, Stephens surrendered her serve again in the seventh game to hand Tig a 5-2, double break lead. When her backhand floated long on set point, Tig had won a routine 6-2 set and was poised for the upset.

Patricia Maria Tig of Romania plays a forehand against Maria Sakkari of Greece in their second round qualifying match during day one of the Mutua Madrid Open tennis tournament at the Caja Magica on April 30, 2016 in Madrid, Spain. . (Photo by Clive Brunskill/Getty Images)
Patricia Maria Tig of Romania plays a forehand against Maria Sakkari of Greece in their second round qualifying match during day one of the Mutua Madrid Open tennis tournament at the Caja Magica on April 30, 2016 in Madrid, Spain. . (Photo by Clive Brunskill/Getty Images)

Tig continues to build her momentum, holds nerve to advance

Sensing her strong position, Tig wasted no time stretching her advantage, replicating the first set by breaking Stephens to open the set. If any nerves showed, it came in the second game which lasted 15 points and saw the Romanian fight off Stephens' first two break points of the match to hold and maintain her edge, which was now at 2-0.

Neither player did much of anything in the ensuing service games, but Stephens created what would be her last two break opportunities, but was unable to convert on either, Tig now two games asay from the massive upset at 4-2. Stephens wasn't her normal self, spraying errors on routine shots and after holding to draw to within 4-3, she lost the final eight points of the match, Tig advancing in straight sets.

Tig steady all across the board, faces Keys next

The 134th ranked qualifier only got 54 percent of her first serves in, but won 22 of 28 first serve points for a 79 percent clip while also guarding her second serve well, a 67 percent rate(16 of 24). Not giving Stephens many looks to break, Tig saved all four break points while taking four of her nine chances that the American gave to her.

She won 64 total points to Stephens' 43. The 21-year-old is becoming one of the talking points of this 2016 Mutua Madrid Open draw as she followed up her first round win over Daria Kasatkina with a 6-2, 6-3 with this victory over the number 16 seed. Tig has qualified for main draws in St. Petersburg and Charleston this year, but the result in Madrid has come out of the blue. She'll next face another American, Madison Keys In the third round.