Chennai: Royal Challengers Bangalore are high on confidence after four wins in six matches but captain Anil Kumble expects struggling Chennai Super Kings to come hard on them in their Indian Premier League match in Channai on Wednesday.

"It will be nice to start the second half of tournament with a win, but I expect the Chennai Super Kings to come hard at us and we need to keep our focus. The Super Kings are a good side and they have done well in the last two seasons, but they are rather off-colour this time," Kumble said after his side's strenuous practice session.

RCB have been bolstered with the joining of Englishman Kevin Pietersen and Australian Cameron White but Kumble said it would be a tough job for him to fit the duo into the team.

"As a captain, it is a tough job for me with KP (Pietersen) and White having joined us. We need to take a different approach from here on and also have to decide how to fit in these two players," he said.

"We are blessed to have them, but we are also looking at how to fit in other domestic players. I am quite happy with our top order batting and Twenty20 is mostly about getting runs on the board," he added.

CSK opener Matthew Hayden conceded that his side were struggling in the tournament but confident that they would get back to winning ways.

"True, the momentum has had a negative impact on us, but Twenty20 is very fickle. The momentum can quickly change. It all boils down to individual players challenging themselves to lift their game," Hayden said.

"If you look back, most of our matches could have gone either way. Against RCB in Bangalore, we were in control until 16th over, but allowed the match to slip away. In other games too, we were in with a chance. It was unfortunate to have lost the match in Super Over to Kings XI Punjab," he said.

Hayden denied that his use of Mongoose bat had affected his rhythm.

"I need to get into back half of the game and personally, I would like to carry my bat through the innings," he said.

On frequent changes in playing XI, he said the team management went about it according to condition of wickets.

"We had different conditions and so you pick your best side for the game. We had slow pitches and bouncy tracks. So obviously, you cannot go in with the same combination for all the matches," he said.

Asked about the possibility of a spinner opening bowling, he said, "Yes, speed is the key, but you have seen teams opening the bowling with spinners. No doubt, it is a risk worth taking, but it can either come off in a big way or will not."