Vettori said the opening pair set the tone with their power-hitting at the MA Chidambaram Stadium Friday, and made it easier for the RCB bowlers.
"We have played very well. Once again Chris Gayle and Mayank Agarwal gave us a good start in the beginning and it was so much easier for us," Vettori said after his team restricted Mumbai Indians to 142 for eight after posting an imposing 185 four four on the board.
"Once you put that kind of performance it was going to be tough for Mumbai Indians, particularly when we have got some economical bowlers," he added.
Vettori felt it was a good toss to lose as he too would have opted to bat first in the Chepauk pitch.
"Looking at the statistics of teams winning batting first at Chennai, we wanted to bat first. It worked out and some days it does not work out," he said.
Gayle has done bulk of the scoring for Bangalore but Vettori was confident that other batsmen of the team such as AB de Villiers were capable enough to help them lift the trophy.
"Chris had fired most of the times when we picked him to play. AB has had a good tournament too and many guys in our team could do it. But obvious we have Chris Gayle as well," he said.
Vettori said he doesn`t want to analyse the game against Mumbai Indians too much and hoped his batsmen would come good against Chennai Super Kings in the summit clash.
"In 20-20 cricket it works on some days and players perform some days. We will not be analysing too much in to these things. I hope the batters turn up (in the final) and come up with good performances," he said.
Asked if Tendulkar`s wicket was crucial, the Kiwi said Mumbai Indians had a number of quality batsmen up its rank who could have changed the complexion of the game.
"They had other good players too. Franklin can play very well and Rohit Sharma is a good batsmen and Pollard was there.
It is important that we were aware of their abilities to come hard at us."
Vettori also heaped praise on spinner Syed Mohammad, who dismissed Sachin Tendulkar at a crucial juncture.
"He did a great job. He had Tendulkar`s wicket with intelligent bowling. He is a very confident guy and sure of his game in similar situations. He is not overawed by these," he said.