"We did not get a good start. We got some partnerships going, but also lost wickets regularly. We capitalized on the Power Play to get to a total, which I thought was par for the course. But in these conditions you need to get early wickets. We did not get those," Dhoni said.
"If we had got wickets with the new ball things would have been different. Though we got three-four wickets in a clutch, it was too late to make a difference," he conceded.
He said fielding alone cannot be blamed for the defeat while admitting his side was not the best in this department.
"This team is the best in batting and we have the best bowlers, but we are not the best fielding side in the world. We need to score 20 more runs to make up for the fielding lapses," the India stumper, who became the highest ODI run-getter this year, said.
Dhoni, whose late-order hitting fetched him 107 in 111 balls to lift India to 301 for seven, said he had batted at various positions from number three to seven this year and is happy to have performed consistently.
"But I have to thank my teammates. The openers have given good platforms for others to build," he said.
He also praised the performance of youngsters Virat Kohli and Suresh Raina, saying both batted very well in making half centuries.
"Virat batted very well. When he came in there was a lot of pressure. The spinners were bowling well and the fast bowlers were using the bouncers. He is also an excellent fielder either inside or outside the circle. It's exciting to see characters like him," he said.
"Raina is a batsmen who, after he is well set, goes for the big shots, sixes and fours. That's the hallmark of his batting," he added.
Kohli scored 54 and helped Dhoni steady the innings from 81 for three while Raina slammed a quick-fire 68 in 55 balls, inclusive of four fours and three sixes, and also put on a century stand for the fifth wicket with his captain.
Dhoni also praised Sri Lanka opener Tillakaratne Dilshan, who cracked his second successive ODI hundred -- 123 to follow up on his career-best 160 at Rajkot in the series opener.
"He's a very aggressive batsman and has been very consistent. On his day he can be dangerous. He has got all the shots -- the cut, the pull or the shot over the bowler's head."
About new Sri Lankan spinner Suraj Randiv, Dhoni said he bowled well, but the situation also helped him with India concentrating on building the innings after losing early wickets.
"He's good but needs to be seen in other conditions. Today he had everything going for him. There was not much pressure."
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