Lorenzo Insigne orchestrated both Napoli goals as the southerners achieved a club record 91 points for the season -- four behind champions Juventus.
Chasing 175 for victory, the Mumbai batting faltered against the Delhi spinners to be bowled out for 163 in their final league encounter of the cash-rich Twenty20 tournament.
The 25-year-old Yates extended his advantage as Froome, 32, lost more time and is now nearly three minutes behind his compatriot.
Farah, who finished third in the London Marathon last month, deployed his famous finishing kick to surge past Uganda's Moses Kipsiro with 100 metres left to win in a time of 28 minutes 27 seconds.
The win lifted Neuville top of the championship standings after six of the 13 events on the calendar with the Rally of Italy in Sardinia next up in two weeks.
He will next seek an 11th French Open crown to match the 11 he already owns from Monte Carlo and Barcelona.