The young Brit – who is supported by the LTA Men’s & Women’s Programme – knocked out the former world No.35 7-6(2), 5-7, 6-1 to seal the biggest win of her career so far.

Lacy is now set to take on either Ashlyn Krueger or Sachia Vickery in the second round of the Lexus Surbiton Trophy and is one of 12 Brits to feature in the main draw this year.

Having fought her way through qualifying earlier this week, Lacy appeared full of confidence and playing with a lot of aggression from the back of the court.

Despite going a break down in the first set and with Brengle serving at 5-4, she battled her way back onto level terms. The young Brit reached another level in the tie-break, showing great variation and movement to capitalise on a slump from the American and win a hard-earned set.

The 18U Junior National Championships winner had led 4-2 in the second, but as a few errors started to creep into the young Brit’s game, the experience of Brengle shone through to force the decider.

After a disappointing end to the second set, it was important that Lacy got herself firing again in the third and she did just that – breaking on the opening game after another quality rally ended with the American firing long.

This would be one of four breaks the 16-year-old would go on to clinch in the final set, with Brengle struggling to get any advantage off her serve. In the closing stages of the match, Lacy showed maturity beyond her years, saving some of her best tennis for last. A couple of aces and a series of winners off both wings brought an end to the best result of her career to date and first against a player in the top 100.