Williams said 'mystery' spinner Narine's four overs always play crucial role in his team's success, hence benefiting the other bowlers.
"The opposition always looks to play Narine out and not give him a wicket. So, his four overs are very crucial and it puts a lot of pressure on the batting side. They try and take the advantage off the other bowlers and lose wickets in doing so," Williams said at the pre-match press conference here today.
"We have three bowlers -- Samuel Badree, Ravi Rampaul and Sunil Narine -- who were part of the World Twenty20 winning West Indies side. With 12 overs up their sleeves among themselves, we are generally confident of defending 150-160," the coach said.
After thrashing Chennai Super Kings by eight wickets in their last group game, T&T will take on Mumbai in the second semifinal and Williams said they were confident of toppling the former champions and IPL title holders.
"This pitch is more like home. We're accustomed to that sort of low bounce and skiddy pitch and we prefer to play the big game here," he said.