Sydney: China`s Li Na wasted little time in advancing to her fourth Australian Open semi-final with a seemingly effortless 6-2 6-2 demolition of Flavia Pennetta on Tuesday.

The 31-year-old, who has reached two of the last three finals at Melbourne Park, blasted the 28th-seeded Italian off the court in 66 minutes with a strong first serve and barrage of powerful ground strokes.

Pennetta`s service game also fell apart, winning 25 of 54 points on her own serve in the entire match, which allowed Li to jump out to a 5-0 lead in the first set and 4-0 in the second.

Li clinched victory with a forehand winner to set up a semi-final against either 14th seed Ana Ivanovic or Canadian Eugenie Bouchard, seeded 30th.