MIAMI, FL, USA - Bianca Andreescu just keeps writing dramatic new chapters in one of the season's most compelling tennis stories - this time coming back from the brink of defeat, saving one match point en route to erasing a set and 1-5 deficit, to triumph 4-6, 7-6(2), 6-2 over Irina-Camelia Begu for the second time this month.

Two weeks ago, though few would have foreseen it at the time, it was a win over the Romanian from a set down that was the first step in one of the most remarkable title runs seen on the WTA Tour, Andreescu backing it up with upsets over Garbiñe Muguruza, Elina Svitolina and Angelique Kerber to lift her first trophy in Indian Wells as an unseeded wildcard.

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The 18-year-old arrived in Miami still without the benefit of a first-round bye - the previous edition of the rankings were used to determine the tournament's 32 seeds - and thus taking the court just four days after winning the biggest final of her career.

For a set and a half, it showed. Begu - having come so close to defeating Andreescu a fortnight ago - was far from overawed by her opponent's newfound status, and came out with a decisive gameplan: to load up her serve and groundstrokes with heavy topspin and thus smother the Canadian's shotmaking. Begu was also sharp to take her own opportunities when they hoved into view, too, firing a backhand winner on her first break point to capture the Andreescu serve immediately.

That would prove decisive in the first set: a significantly less sharp Andreescu's best chance to get back into it would come in the eighth game, but two forehands - one a sitter after stellar defensive work - flew long on both of the teenager's break points. Two games later, clutch serving saw Begu over the line.

Neither could Andreescu take advantage of a sequence of three consecutive breaks to open the second set; indeed, it was Begu who regained her equilibrium quickest, regaining control of her game to leap out to a 5-1 lead. Down 4-1, having just committed her fifth and sixth double faults to fall behind a double break, the Indian Wells champion showed her frustration during an exchange with coach Silvain Bruneau, exclaiming: "Every time I try and do the right thing, it never goes my way… I'm getting so mad at myself."

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A similarly cathartic on-court coaching conversation had spurred a turnaround against Kerber in the Indian Wells final - and so it proved again today. At the very edge of defeat, Andreescu came up with her best tennis of the day, clinging on with bravely struck groundstroke power and saving a match point at 2-5 with a ferocious return.

Hitherto, Andreescu's magic had been intermittent - but now the rejuvenated World No.24 managed to sustain it, reeling off five consecutive games against a shellshocked Begu, now prone to ill-timed double faults herself. With her full repertoire returning to working order, Andreescu delivered a masterclass of a tiebreak to level the score: a reflex backhand volley, a fiendish forehand slice that tangled Begu up completely and two exquisite dropshots.

As the match headed into a decider, a fifth double fault to immediately concede her serve to love illustrated that Begu had not quite recovered from the second set - but even when the 28-year-old regained some composure on serve, it wasn't enough to halt the Andreescu juggernaut.

Buoyed by a crowd that had roared her comeback on, the youngster was thoroughly dominant, dropping just four points on serve throughout the third set. 

Seizing a double break as Begu's groundstrokes became increasingly shank-prone, Andreescu closed out an astonishing victory in style with a love hold, completing the win after two hours and 33 minutes. Up next as she bids to keep her winning streak alive is another player with whom Andreescu has recent history: No.32 seed Sofia Kenin, her conqueror in last month's Acapulco semifinals and one of only three players to have scored a win over the Canadian supernova in 2019.