Confident Swiatek rediscovers ruthless best in Rome

However, she lost her invincibility on the surface last year - unable to win a clay-court tour event before losing in the Paris semi-finals.

Swiatek tweaked her playing style under previous coach Wim Fissette, who tried to implement a more aggressive approach from the baseline.

But she ended up losing confidence in what they were trying to achieve and quickly became ragged when matches started going against her.

It has been a case of going back to basics with Roig, who she snapped up after his short stint with Britain's Emma Raducanu ended.

Swiatek played with the high intensity and relentlessness demanded by Roig from the start against Pegula - but, crucially, she always looked stable in her shot-making.

Playing with more patience and a higher margin for error meant she was able to draw mistakes from the 2024 US Open finalist.

Pegula was well below par on a surface she does not favour, but the manner in which Swiatek refused to let her level drop was a sure sign of her increasing assurance.

Swamping Pegula's second serve with deep returning was another notable feature.

Tougher challenges will surely lie ahead in Rome - either Kazakhstani second seed Elena Rybakina or Ukraine's seventh seed Elina Svitolina await in the semi-finals - but the signs for the rest of the French Open challengers are beginning to look ominous.

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