Bowlers have been blasted around the R Premadasa Stadium so far in this tournament, but Jaydev Unadkat has a solution: variations.

Twice in the past week, good totals have been chased down. In the six batting innings so far, sides have struck 70 or more inside the Powerplay thrice. Unpredictability on the bowlers' part may help stem the flow of runs, Unadkat said. His own success against Bangladesh on Thursday, was partly due to his varying of lengths; two of his three wickets came off short balls, the other off a yorker.

"Variations are the most important part of the game," he said ahead of the match against Sri Lanka. "To play with batsman's mind, you need variations. When the batsman is expecting something and you do it differently, we are successful as bowlers. The wicket looks very good for batting from ball one. I haven't played here before in limited-overs cricket. The ball is coming on nicely, there's good bounce and that gives batsmen freedom. Variations is not just about bowling different balls, it is important to vary the lengths. Not allowing them to premeditate a shot, I think that's how we are going to try."

Slower balls have been somewhat effective in the tournament so far, though not as much as they often are at Khettarama. What has more commonly yielded a wicket have been cutters - especially those bowled by Mustafizur Rahman. On Saturday, Mustafizur bowled Danushka Gunathilaka with a leg cutter, and later had Kusal Perera caught off a similar delivery. Though not as proficient in the art as Mustafizur (perhaps no one in world cricket is, presently), Unadkat may himself follow the lead of the Bangladesh quick.

"[Cutters] suit my plan. If the wicket is suitable for that, I will do that," he said. "Having said that, it still is important to vary. Cutters are only useful when the batsman doesn't expect it. So if the wicket is spicing up a bit - if I see the wicket is gripping a bit - definitely then that's the way to go. That has been my strength in this format of the game in the past couple of years, I have always banked on that. In the first game also, we tried those, but it is only successful when the batsmen don't expect. In T20s, you are going to be under pressure 24 times."

Though other spinners have been expensive so far during the Nidahas Trophy, Washington Sundar - India's offspinner - has maintained an economy rate of under seven. He has been particularly good in the previous match against Sri Lanka, dismissing Kusal Mendis cheaply, before taking the wicket of the marauding Kusal Perera later in the game. The control Sundar has exerted on an innings can sharpen the menace of the bowler at the other end, Unadkat said.

"I think what benefits us bowling together is Washington contains the batsmen. As an offspinner, it is difficult at times to contain, because the batsmen just blast from the start. He varies his pace really well, that stands out for me. He keeps it simple, when a bowler is containing from one end, so the batsmen do come under pressure and target you - they try to go harder than they usually should. That benefits us as bowlers."

Andrew Fidel Fernando is ESPNcricinfo's Sri Lanka correspondent. @andrewffernando