The Serbian’s Round of 16 success over Albert Ramos-Vinolas sealed a third straight win for the first time the Australian Open in January.
Djokovic – who has made the final in all of the last four years in Rome – now takes on Japan’s Nishikori, who he beat in his opening match at the Madrid Open last week.
Nishikori has seen off Feliciano Lopez, Grigor Dimitrov and most recently Philipp Kohlschreiber to make this stage of the tournament.
He has only ever beaten Djokovic twice in 14 career match-ups, his last win coming in 2014 – losing 11 meetings since then.
Awaiting in the final four is likely to be none other than Rafael Nadal, the seven-time Rome winner who faces Fabio Fognini earlier today.
By the time Djokovic steps out on court, the 30-year-old will be aware of the opponent he is playing to face – but can he move a step closer to a fifth straight final at Foro Italico?
How to watch Novak Djokovic vs Albert Ramos-Vinolas on TV
Sky Sports are carrying all the coverage of this week’s Italian Open.
Today’s coverage begins at 11am on both their two channel, running until 1.55pm on Sky Sports Main Event (Sky channel 401, Sky HD 855, Virgin channel 511, BT TV 402) and until 5pm on Sky Sports Arena (Sky 408).
The Arena channel’s coverage will also resume at 8pm, running until 10pm.
Djokovic’s clash with Nishikori on Centre Court won’t start any earlier than 3pm UK time.
How to watch Novak Djokovic vs Albert Ramos-Vinolas online
Sky’s coverage of the Italian Open means that all the action can be followed on your desktop or laptop via the Sky Go app, which if you’re an existing customer, is also available on iOS and Android smartphone and tablet devices.
Sky Go is also available on a number of platforms including Amazon Fire devices, iPad, Mac computers and laptops, Playstation 3, PS4 and Xbox One.
The Sky Sports app, available to download on iOS and Android devices, will also be providing live text coverage and updates.
If you’re not currently a Sky Sports customer but can’t stand to miss out on the action, you can add the channels to your box via a NOW TV subscription.
Day passes, which let you add Sky Sports channels for 24 hours, start at £6.99 a day, with a weekly pass starting from £10.99, and no locking in to a contract.
NOW TV doesn’t even require a typical television to use, as it is also available on a NOW TV Box, Chromecast, PS4, PS3, Xbox One, Xbox 360, Roku, LG Smart TV, PC or Mac, and selected mobile and tablet devices.