Sachin Tendulkar has said the upcoming Test series against New Zealand is very important for the team from momentum building perspective before the 2011 World Cup.

Tendulkar said after the recent win against Australia, it is now time to focus on the New Zealand series.

"I would like to think about the next three test matches that we play, and when we go to South Africa or just before that.

"Once we are through with New Zealand, then we can think about South Africa and that is the case with the World Cup as well," said Tendulkar.

The Master Blaster was addressing media persons on the sidelines of an endorsement.

"But before we start playing the World Cup tournament, there is a lot of cricket left and that is what we would want to focus on, because I believe in momentum, and that momentum to keep with us, is really important.

"So, right now it is time to focus on New Zealand," he added.

Tendulkar also revealed the logic behind choosing a particular brand for endorsement.

"Whenever we think of associating with any brand, then obviously we check the reputation and the value, and whether I want to endorse that brand or not.

"And similarly, they want to take me or not is very important," he said.

Tendulkar also described the win against Australia as ''unbelievable'' and praised the match-winning knock of VVS Laxman in the Mohali Test as ''terrific'' sportsmanship.

New Zealand is scheduled to play three Tests followed by five One-Day Internationals (ODI) matches against India beginning on November 4.