Maria Sharapova survived a US Open first round scare on Monday when she clawed her way back from a set and a break down to defeat gutsy British teenager Heather Watson, the world 104.
Former world number one Sharapova, the third seed and 2006 champion, won 3-6, 7-5, 6-3 but only after being stretched by the 19-year-old 2009 junior champion who was making her main draw debut.
Exactly 100 places separate the two women in the rankings, but Watson wasn't overawed until the final set when Sharapova, a French Open semi-finalist and Wimbledon finalist this summer, switched on the turbo-power.
The Russian finished with a blistering 41 winners to Watson's nine although her 58 unforced errors and eight double faults were hardly the statistics of a champion-in-waiting.
"It was one of the toughest (opening matches) that I've had. Obviously not really knowing too much about my opponent and not facing her before. She just came out and played really smart," said Sharapova, who has yet to lose a three-set match this year.
"There's no doubt that I wasn't playing my best tennis. She was smart in making me hit another ball. I was making so many errors out there. She stuck to her game plan. She kept grinding."
Sharapova was plagued by mistakes in the first set on the showpiece Arthur Ashe stadium. She fell 4-1 down, but managed to save two set points in the ninth game before a netted second service return gave Watson the opener.
The Russian also dropped serve in the opening game of the second set before she hit back to lead 4-1.
Back came the battling Briton as Sharapova double-faulted in the seventh game to surrender the break.
But at 5-6 down, Watson's nerve finally failed her.
A handful of silly errors allowed Sharapova, who had been a set and 1-4 down to French teenager Caroline Garcia at Roland Garros, to level the tie.
The Russian was quickly into a 3-0 lead in the decider as her young opponent wilted under the barrage of groundstrokes as well as the Sharapova ear-piercing vocals.
But from 1-4 down, Watson recovered the break to go to 3-4 before another thrilling twist saw Sharapova once again summon all of her renowned fighting spirit to break again for a 5-3 lead.
Watson saved a match point but a long forehand confirmed her defeat and a place for Sharapova in the next round where she will face Anastasiya Yakimova of Belarus, who beat Thailand's Noppawan Lertcheewakarn 6-0, 4-6, 6-3.
Despite her victory, Sharapova's customary on-court shrieking was not to everyone's liking.
Star British golfer Lee Westwood wrote on Twitter: "Glad Sharapova's not playing in Crans this week! They'd hear her in Geneva! Come on Watson finish her off for the sake of our eardrums!"