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The former US Open champion came from a set down to win 4-6, 7-6 (8-6), 7-5, emerging victorious after two hours and 42 minutes.

Pegula stamped her authority on the game from the start, winning break point in the opening game and remaining in control despite a spirited comeback from Raducanu.

However, the Brit built on her improved display in the second set, trading blows with the world No.5 and coming out on top to take the game to a decider.

Raducanu looked set to close out the contest as she claimed consecutive break points, but the American showed her class to drag herself back level.

But it would be Raducanu who would emerge victorious, meaning there will be three British women in the quarter-finals of the competition for the first time since 1978.

Raducanu's victory saw her reach her first quarter-final at Eastbourne.

The Brit's success was also the first time she has won a match on the WTA Tour after being a match point down.