MELBOURNE, Australia - The first two quarterfinals at this year's Australian Open take to the court on Tuesday, with Li Na meeting Agnieszka Radwanska and Maria Sharapova facing fellow Russian Ekaterina Makarova.
Rod Laver Arena
 Agnieszka Radwanska (POL #4) vs.  Li Na (CHN #6)
Head-to-head: Li leads 5-4
Despite bringing some fairly formidable statistics into her quarterfinal with Li Na, Agnieszka Radwanska has crept under the radar somewhat in Melbourne. Since the start of the year, Radwanska's record reads: played 13, won 13; sets for 26, sets against 0. And judging by her straight set dismissal of Ana Ivanovic in the last round, she is showing no sign of running out of steam.
Li's start to 2013 has been far from shabby either. After getting underway with a title on home soil in Shenzhen, the Chinese No.1 reached the semifinals in Sydney - losing to Radwanska - before breezing through the opening week in Melbourne without dropping a set. While Radwanska's win in Sydney gives her bragging rights, Li does not need to go too far back to locate some confidence-boosting memories of her own, having won handily in all three of the pair's hardcourt meetings last year.
 Maria Sharapova (RUS #2) vs.  Ekaterina Makarova (RUS #19)
Head-to-head: Sharapova leads 4-0
Regular patrons at Melbourne Park will get a sense of déjà vu when they settle down for the third match of the afternoon session. Twelve months ago Maria Sharapova and Ekaterina Makarova squared off for a place in the Australian Open semifinals and on Tuesday they will do so once again. On that occasion Sharapova triumphed in straight sets, which she followed up by reaching the final where she was defeated by an inspired Victoria Azarenka.
If Makarova is to avoid a repeat performance and reach her maiden Grand Slam semifinal, she will need to serve well; Sharapova has dropped just five games thus far - the fewest since the draw was increased to 128 in 1988 - winning 23 of 27 return games. Yet Makarova is no slouch on the return herself - she broke No.5 seed Angelique Kerber four times in two sets - and this, allied with her formidable artillery from both the back and forecourt ensures she remains a very live underdog.