Virat Kohli marked his 35th birthday with his second century of the World Cup and Ravindra Jadeja claimed five wickets as India thumped South Africa by 243 runs in a contest featuring the top two teams in the tournament at the Eden Gardens on Sunday.

South Africa's chase of 327 began shakily as they lost half their side cheaply for 40 runs inside 14 overs as Jadeja (5-33) and Mohammed Shami (2-18) wreaked havoc before the Proteas fell to only their second defeat, dismissed for 83 in 27.1 overs.

Jadeja was the pick of the bowlers, shattering the stumps of three batsmen, while Mohammed Siraj (1-11) and Kuldeep Yadav (2-7) also played their part in the big win.

Kohli's unbeaten 101 contained 10 fours and left him level with Indian great Sachin Tendulkar on 49 one-day international hundreds as he continued his superb form by taking his tally past 500 runs in the tournament.

He dropped anchor in a solid third-wicket stand of 134 with Shreyas Iyer, who hit 77 with seven fours and two sixes, before making his ton in the 49th over as India finished with 326-5 on a slow Kolkata wicketwith late hitting by Jadeja (29 not out).

Both teams have qualified for the semi-finals and Sunday's game was touted as a dress rehearsal for the title clash later this month and it was India who took control early and set up their eighth successive victory.

They elected to bat first after winning the toss and took advantage of some wayward pace bowling by Marco Jansen to make a blazing start but skipper Rohit Sharma fell for a 24-ball 40 as he looked to launch first-change Kagiso Rabada over mid-off.

After reaching 91-1 in the powerplay, the hosts lost opener Shubman Gill (23) to an unplayable delivery from Keshav Maharaj in the 11th over as South Africa brought the run-rate under control with spin.