HAMILTON, NEW ZEALAND, MAR 10 - India's remarkable turnaround at the Cricket World Cup continued on Tuesday with a fifth consecutive win ensuring the defending champion will top its pool heading into the quarterfinals.

India beat Ireland by eight wickets to remain unbeaten, a dramatic change after they entered the World Cup without a win in a competitive match in the previous two months on Australian soil, spanning four test matches and a limited-overs tri-series against Australia and England.

"We have been here for over four months, we had to sacrifice somewhere," India skipper Mahendra Singh Dhoni said. "I knew it (form) would be back when the World Cup started.

"I'm glad all of us have stepped up. It feels good — we just have to take the momentum forward."

Shikhar Dhawan scored 100 and Rohit Sharma hit 64 in a 174-run opening partnership as India reached 260-2, chasing down Ireland's 259 with 13.1 overs remaining.

Ireland's push for a place in the quarterfinals will continue on the weekend against Pakistan.

India will stay atop Pool B regardless of the outcome of its last group match against Zimbabwe.

Ireland must now beat Pakistan in the last match of the pool round at Adelaide on Sunday, or at least take a point from that game, to have any chance of progressing.

"It's all about being mentally fresh for that game in Adelaide," Ireland captain William Porterfield said. "It's a winner-takes-all for us."

India achieved their win with the kind of efficiency which has marked its progress through the tournament. After Porterfield made 67 and Niall O'Brien scored a run-a-ball 75 to give Ireland hope of a competitive total, India took seven wickets for 53 runs. Fast bowler Mohammed Shami had the best return of 3-41, and spinner Ravi Ashwin took 2-38.

Ireland's total was also the highest score by any team against India in Pool B. India have in common with Pool A leader New Zealand the fact they have bowled out their opponents in all five matches: Pakistan for 224, South Africa for 177, United Arab Emirates for 102, and the West Indies for 182.

"It's a good stat. It means the bowlers are really doing the job for us," Dhoni said. "It's a remarkable difference, they've really stepped up. Not just the three fast bowlers, the spinners as well ... looks like a happy unit."