Sri Lanka overcame adverse playing conditions and a poor start on the first day of their rain-affected ODI against West Indies to achieve a victory that has all but put them in the final of the tri-series, a result the captain Angelo Mathews said had proved the character of his side.

Play was abandoned on Sunday with Sri Lanka 60 for 3 in 19 overs. They had to restart their innings, which was reduced to 41 overs, on Monday knowing that anything less than a strong batting performance would hurt them under the D/L method. Under Kumar Sangakkara's guidance, Sri Lanka made 159 in 22 overs.

"We had a team talk, and we needed to get runs. Especially with D/L, batting first is a disadvantage," Mathews said. "It is tough to play around rain delays batting first. We had to get the runs, and I am glad that we got the runs.

"Very pleased with the boys. They showed a lot of character. Especially on the first day. I thought Sangakkara batted brilliantly, he held the innings together."

Sangakkara batted through the innings, converting a cautious start on Sunday into an unbeaten 90 off 95 balls on the reserve day. He helped Sri Lanka take 72 runs off the last six overs. "I think the wicket was quite spongy. There was a slow high bounce. It needed patience at the start and slogging at the end," Sangakkara said. "If you hang in there, with the new rules, and the wicket getting better, you can get the runs.

"The real decision is, when the going is tough, are you going to absorb the pressure or are you going to attack? Batting first, you can absorb the pressure and then catch up in the end. If you have wickets in hand, the advantage is with you. On tough wickets like this, being there in the end helps."

Sri Lanka were aided by a West Indies bowling performance that was poor compared to the effort on the first day of the game. Apart from their inability to contain the batsmen, West Indies' bowlers conceded 31 runs in extras, 24 of which were in wides.

"We undid the work we did yesterday. It wasn't right on our part. When you set plans, you have to bowl the plans. We were all over the shop," their stand-in captain Kieron Pollard said. "If we are honest with ourselves, our bowling was not up to the mark. Thirty-one extras is totally unacceptable."

The batting also let the home side down. Chasing a revised target of 230 in 41 overs, West Indies slumped to 31 for 4 in the ninth over. Devon Smith made a 14-ball duck. The innings was stabilized by Darren Bravo and Lendl Simmons, who made half-centuries, but after that stand another collapse followed and five wickets fell for 23 runs.

"Bravo and Simmons brought us back, but if we are totally honest with ourselves, myself included, we haven't batted well," Pollard said. "We always put ourselves in these situations. As cricketers, we need to find a way out. It should not have come down to this."

West Indies now depend on Sri Lanka beating India in the final league game on Tuesday in order to make the final of the tri-series.