Noting that the team's sloppy fielding is a big "concern", he added that the bowlers need to perform better while bowling in the middle and slog overs.
"Definitely, we can improve in the bowling department, especially in the middle overs and slog overs. Each and every batsman can also be consistent. We also need to raise our fielding standards; it has gone down a bit, but you have to be at your best in a tournament like this.
"We have missed quite a few run-out opportunities and dropped a few catches, and that could prove crucial in a big tournament like the Champions Trophy. So we are a bit concerned and putting loads of effort in it," said Dhoni in Mumbai on Thursday, ahead of the team's departure to South Africa for the September 22 - October 5 tournament.
Despite being ranked No 2 in the ICC rankings and tipped as one of the favourites for the title, Dhoni is wary of taking any team lightly.
"Each and every team that comes for the Champions Trophy is the best in the world, so every team has to be taken seriously. It doesn't really matter whether you are playing Pakistan or Australia, you want to win every game. So we are just looking to do the things that we need to do, like preparing well for the Champions Trophy," said India's captain.
India are placed in a tough group and will face mighty Australia, Pakistan and the West Indies in the group matches.
"We expect tough competition in the Champions Trophy. We are in a tough group so we can't afford any slip-ups and have to perform at our best right from the start," said Dhoni.
Much is already being made of India's high-voltage clash against arch-rivals Pakistan in Centurion, on September 26, but Dhoni is not reading too much into it.
"We prepare in the same way for every team, whether we are playing Pakistan, Australia or Zimbabwe. It does not really make much of a difference, as we want to win each and every game at the international level. We can't afford to take any side lightly, so we will be prepared for all sides."
He also feels that Rahul Dravid's inclusion is a big boost for the side in the normally difficult conditions encountered in South Africa, where pitches favour the bowlers.
"It is good to have players who have faced these conditions and situations and have been in pressure under numerous occasions. That is one area where they are a real big asset to the side. Rahul bats at number three especially in South Africa where the conditions are helping fast bowlers. He is the batsman that you want to be at number three," he said.
But the rest of the batting order he clarified is not fixed and could change depending on the conditions.
"We keep fluctuating batting positions at number three, four and five depending on the start we get. So depending on the situation we promote the best-suited batsman to that particular position. So there is nothing like a fixed batsman and we keep changing the batting order according to the situation."
Dhoni made it clear that he would continue to start with three fast bowlers because he believes that combination works best for his side.
"Our bowling combination would depend on the wicket but our normal strategy has been to play four specialist bowlers and one part-time bowler so we can accommodate an extra batsman. One thing is sure we need three fast bowlers because it is very difficult for the spinners to bowl in the Power Play overs.
In the Champions Trophy you will definitely see three fast bowlers, but the question will be whether to play one spinner or two spinners."
Asked how his batsmen would cope with short-pitched bowling, which caused the team's early ouster from the Twenty20 World Cup, Dhoni said the strategy is different in a 50-over game when compared to Twenty20 cricket.
"I think in T20, you hardly have time to adjust, you look to go after the bowler. But in a 50-over game you have time to pick and choose and leave the ball if it is a good bouncer. In a T20 game even if it is a short-pitched delivery at a good pace you look to go after it.
"At times we have seen bowlers who can bowl at 140 plus have been effective with the bouncer and if they are accurate they can restrict the batsman and have got wickets at the same time. It is a problem that not only the Indian team faces but all the other teams also face."
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