23:15 CET - Welcome back to the Tennis Tracker tonight, as the fourth round finally begins at the Australian Open, with several excellent clashes to look forward to in the second week of the opening Grand Slam of the year.
Up first on Rod Laver Arena at 01:30 CET, world number one Aryna Sabalenka comes up against young starlet Victoria Mboko in a fascinating clash, which is then followed by fellow number one Carlos Alcaraz's meeting with Tommy Paul.
The night session begins at 09:00 CET, with home favourite Alex de Minaur clashing with the in-form Alexander Bublik, in what should be a fantastic occasion. The final match on the main court sees two players who have started the season superbly, Mirra Andreeva and Elina Svitolina, go head-to-head.
The singles action starts on Margaret Court Arena at 04:30 CET, as Coco Gauff takes on Karolina Muchova in another excellent match. That is swiftly followed by a match-up that proved to be so captivating on several occasions last season, with Daniil Medvedev facing Learner Tien. Prepare for a slugfest.
On John Cain Arena at 03:00 CET, another wonderful young player, Iva Jovic, comes up against Yulia Putintseva, with Alexander Zverev butting heads with Francisco Cerundolo afterwards.