Both Stephens and Ostapenko had put previous poor form in 2018 behind them in this tournament, but there were errors aplenty from both players in an opening set that featured eight breaks of serve.

After twice failing to serve it out, Stephens eventually converted her fourth set point in the breaker to move ahead.

The American, who beat Garbine Muguruza, Angelique Kerber and Victoria Azarenka on her way to the final, then raised her game to wrap up victory with ease, proving much more solid in set two as Ostapenko remained erratic.

The match provided a fascinating contrast of styles, with Stephens content to remain largely passive, perhaps owing to the amount of mistakes her more aggressive opponent was making.

Stephens's ability to retrieve balls from all over the court ultimately won the day and the 25-year-old will now hope to kick on after maintaining her 100 per cent record in WTA finals.

Prior to her arrival in Miami, Stephens's win-loss record since the US Open had been a miserable 3-10. Nevertheless, she is now set to enter the world's top 10 for the first time.