India crushed arch-rivals Pakistan and Australia put on another Shane Watson show as the race to the World Twenty20 semi-finals heated up on Sunday.
Virat Kohli hit an unbeaten 78 off 61 balls as India, who would have been knocked out had they lost, bowled out Pakistan for 128 and then surpassed the modest target in 17 overs with eight wickets in hand.
Australia also defeated South Africa by the same margin in the first match of the double-header, after Watson claimed 2-29 and smashed 70 off 47 balls to win his fourth successive man-of-the match award.
Australia restricted the Proteas to 146-5 and won by the 18th over to record their second win in a row in group two, but will still need to beat Pakistan on Tuesday to make the semi-finals.
Australia lead the group with four points, India and Pakistan have two each, while South Africa have lost both matches so far.
India will also have to beat South Africa in Tuesday's second match to remain in the hunt.
A sell-out crowd of 35,000 at the Premadasa stadium, including Sri Lankan President Mahinda Rajapakse, saw India continue their stranglehold on Pakistan in major world meets.
Pakistan have never beaten India in either the 50-over World Cup or the World Twenty20, in which they contested a thrilling final in 2007.
India lost Gautam Gambhir off the second ball of the innings, offering a tame return catch to 20-year-old left-arm spinner Raza Hasan, but Kohli and Virender Sehwag denied Pakistan another immediate break.
Kohli put on 74 for the second wicket with Sehwag and 54 for the unbroken third with cancer survivor Yuvraj Singh, who followed his two wickets and a run out in Pakistan's innings with 19 not out.
The impressive win was set up by the bowlers as seamer Lakshmipathy Balaji claimed three wickets and off-spinner Ravichandran Ashwin took two to leave Pakistan in tatters after they elected to bat.
Shoaib Malik top-scored with 28, but only one other batsman managed to touch 20 in the face of steady bowling by the Indians.
"We did not think too far ahead," said Indian captain Mahendra Singh Dhoni. "I always felt that if you are desperate for a win you put more pressure on yourself.
"But I was glad to see the players were relaxed and I knew that something good will come out of it."
Pakistan captain Mohammad Hafeez praised Kohli's match-winning innings on what he said was a difficult pitch to bat on.
"It was not easy to bat out there and we just did not get the partnerships," said Hafeez. "Kohli was excellent. We were hoping to get him out and put pressure on the rest but we could not do that.
"We also need to improve our fielding but it is a relief that we still have a chance to qualify for the semis."
Watson, the star player of the tournament so far, hit eight boundaries and two sixes to cap another brilliant all-round display.
"It's nice to be able to continue playing well because I know how important my role is," Watson said. "We are doing well but it's still hell of a long way to go in the tournament.
"Facing (Dale) Steyn and (Morne) Morkel was going to be a very big challenge. I knew if we got through the first four overs, the momentum would be with us for the rest of the innings.
South African captain AB de Villiers said he was frustrated by the second defeat after losing to Pakistan on Friday.
"We are very disappointed," he said. "It is just so frustrating when we don't click. I just can't put my finger on one thing, because it went wrong everywhere.
"They did not allow us to get off to a flier and we lost quite a few wickets and that did not give us the momentum. Hopefully it is not all doom and gloom for us."
