After their comprehensive six-wicket win over Kochi Tuskers Kerala in the opening match, RCB was mauled by Mumbai on Tuesday and Vettori realises the importance of the April 14 match against Deccan.
"It's (match against Deccan) an important game for us. After a good start against Kochi, we lost comprehensively to Mumbai last night," the Kiwi left-arm spinner said on the eve of the match.
"I think this competition is about momentum. In such a short period of time between games, if you can get on that (winning momentum), it's going to make things a lot easier," Vettori stressed.
2009 champions Deccan, on the other hand, too would be desperate to return to winning ways after losing their opening two fixtures in IPL IV.
And Vettori admitted that the home team would come hard on them tomorrow, but he said his side was up for the challenge.
"Deccan is going to come harder against us but it's a pretty important game for us too. We will make sure that we come on top against them in tomorrow," he told reporters.
Asked about the injury concern of left-arm pacer Dirk Nannes, the RCB skipper said, "He (Nannes) had a scan this afternoon and the results have been sent to appropriate places. We hope to hear about it (injury) tomorrow morning.
"He hasn't travelled with us and he may definitely be out of the next two games."
Talking about the loss at the hands of Mumbai Indians, Vettori praised Sachin Tendulkar and Ambati Rayadu for their brilliant batting.
"We certainly know we could have played better than that.
I just don't think we bowled as well as we could have after losing Nannes," he said.
Vettori expressed confidence that Zaheer Khan would make a strong comeback in the tournament after the not-so-impressive performance in the first two matches.
"He (Zaheer) has had great World Cup and there's no doubt that he would comeback strongly. I still believe that (Abhimanyu) Mithun is still a very good bowler and he can be a huge asset."
Asked about Sri Lanka Cricket's (SLC) decision to call their players back by May 4 for a preparatory camp ahead of England tour, Vettori admitted that it would be tough to get a replacement for dashing opener Tillakaratne Dilshan.
"He (Dilshan) is a very important player for us in all three departments, batting, bowling and fielding," he said.