Tottenham: Toby Alderweireld
Tottenham are unbeaten since the first day of the league season largely thanks to consistently impressive displays in defence.
But that wasn't the case last campaign despite three of their current back four being the same. The difference has been Toby Alderweireld. The Belgian works well with his full-backs and, more than anyone else, Jan Vertonghen.
Alderweireld has lifted Vertonghen and often, when the 28-year-old slips up, is there to rescue him.
West Ham United: Dimitri Payet
Sadly, West Ham's star man will now be out injured for three months and the fact it comes as a huge blow to the Hammers tells you everything you need to know.
Payet has been one of the top flight's best performers in any position. The Frenchman came with good value for money and has absolutely transformed the West Ham side. Slaven Bilic will need to think creatively to find a way without him.
Tottenham: Dele Alli
From impressing against Real-Madrid during pre-season to his debut, his first start, his first goal and a string of impressive performances, Alli has defied the expectations of many, even earning an England call-up in the process.
To put it into perspective, there have been few midfielders to outperform him in the whole of the Premier League - despite the fact he is only a teenager.