Sri Lanka captain Upul Tharanga said that fearlessness helped his team tighten up their fielding, after their athletic defence of 280 in the third ODI.

Sri Lanka have been routinely woeful in the field over the past two years. The standards hit new lows in 2017, in series against South Africa and Australia, as well as Bangladesh's ongoing tour. The performance in the third ODI was a sharp departure from what had been a worrying trend. A high-energy effort in the infield was backed up by clinical work at the boundaries. Sri Lanka did miss one chance - letting a catch pass between keeper and slip in the first over - but did not commit any major mistakes after that.

"The way we fielded today was really good - everyone was chasing the ball and diving and that's the way we should be fielding," Tharanga said. "We were sloppy in the first game. We gave away too many runs. Not only the first game, I don't think we fielded well in the last two series. The thing that we discussed was to not to be afraid to do mistakes. Sometimes, when we field, we are bit reluctant and worried whether we will miss catches and we position ourselves too deep."

Before the match, cricket manager Asanka Gurusinha had said the team trialled a new training method for fielding, through which they hoped to better replicate match conditions. Early indications are that the new methods have had some impact.

"If you practice those things only it works out in matches," Tharanga said. "There were some good training sessions after the loss. We have attracted lot of criticism that we are not good a fielding side. But we wanted to prove that wrong. We've got to keep doing what we did today and consistently field this well."

Alongside the fielding, Tharanga also credited Thisara Perera's batting for the win. Sri Lanka were in danger of limping through the final overs when Thisara arrived at the crease with the score at 194 for 5. But he played himself in - venturing no boundaries off his first 19 deliveries - before accelerating in the 45th over. He eventually wound up with 52 runs off 40 balls, and was named the player of the match. He had also hit a rapid half-century in the first match.

"I thought Thisara Perera was exceptional today," Tharanga said. "He showed lot of maturity during his knock. He took his time and finished the innings well. He understood his role, and he did this throughout this series. He realised that he needed to come up with big efforts. Today, we were in a tough position. He was the only recognised batter, and his approach was good - he showed a lot of responsibility."

One weakness that has persisted through the series, however, is Sri Lanka's running between the wickets. Sri Lanka lost two batsmen to run outs at the SSC, and of those Dinesh Chandimal's dismissal was especially unusual. Though he grounded the bat after completing a second run, he lifted it as his body crossed the crease, at which point the bails were dislodged. Tharanga was himself run out in strange fashion during the second ODI in Dambulla. He took off for an easy single after the wicketkeeper had misfielded the ball, but was caught by surprise when Mahmudullah threw down the stumps to find him short of his ground.

"My run out in the second game and Chandi's run out today - you can't let those things happen," Tharanga said. "It looked as if we were too casual in our approach. If you take ODIs, you can excuse the run outs towards the end of an innings when you are trying to score quickly. But silly mistakes like these are not good enough."

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