Mahendra Singh Dhoni's India go into a triangular series in Dambulla on Tuesday keen to extend their impressive run in the one-day game in Sri Lanka.
India, who clash with New Zealand in the opening day-night match, have won two bilateral series, a tri-series and the Asia Cup in Sri Lanka over the past two years.
Each side will play the other twice in the preliminary league before the top two qualify for the final on August 28.
India are also fresh from a morale-boosting victory over the hosts in the final Test in Colombo last week, helping them square a three-match series 1-1.
The Indians have rested record-breaking batsman Sachin Tendulkar, key spinner Harbhajan Singh and opener Gautam Gambhir for the one-day tournament, but have enough depth in batting and bowling to test their rivals.
Dinesh Karthik is likely to open the innings with hard-hitting Virender Sehwag in place of Gambhir.
India's batting has been boosted with the return of Yuvraj Singh, who was dropped for the Asia Cup. He has so far scored 7,345 runs in 250 one-day internationals.
Batting is India's main strength, with Dhoni, Yuvraj, Sehwag, Suresh Raina and Rohit Sharma capable of dominating any attack with a rich stroke-play.
New Zealand, who were runners-up in the Champions Trophy in South Africa last year, will test their bench-strength in the absence of skipper Daniel Vettori and aggressive opener Brendon McCullum.
The Black Caps geared up for the tournament in style, winning both their practice matches.
Skipper Ross Taylor, Scott Styris, Jacob Oram and Bradley-John Watling all looked in good form in warm-up games, each scoring a half-century.
Sri Lanka have excellent batsmen in skipper Kumar Sangakkara, opener Tillakaratne Dilshan and Mahela Jayawardene, but need to put in a consistent all-round performance to taste success at home.
Their bowling attack looks depleted in the absence of the veteran duo of off-spinner Muttiah Muralitharan and seamer Chaminda Vaas, who were not considered for the tournament.
The rivals are preparing for the World Cup that will be hosted by India, Sri Lanka and Bangladesh in February-March next year.