Mixed fortunes for Kei Nishikori and Karen Khachanov.
Derek Bilton is on hand with tips from the Rotterdam, New York and Argentina events.
Russian still struggling to get going in 2019.
The big names keep winning in Melbourne.
World number one in fine form already.
Looking for ways to invest your Christmas money?
Who can end the 'golden generation' stranglehold?
Big Russian has big plans.
Greg Rusedski has hailed Karen Khachanov as "a new superstar" of tennis.
Take our 10 teasers to see how much you know about Karen Khachanov.