Sri Lanka captain Sanath Jayasuriya admitted Chaminda Vaas had put the game beyond Bangladesh's reach with his four-wicket first over.
Vaas created history by taking a hat-trick with the first three balls of the match, before grabbing another to leave Bangladesh reeling on 5-4.
"I think Vaas bowled brilliantly and when he got that hat-trick, the match all changed," said Jayasuriya.
Vaas, who was unsurprisingly given the man-of-the-match award, played down his achievements.
"I'm not really interested in records. As long as I am fit and bowling well, that's the important thing," said the 29-year-old, who finished with figures of six for 25.
"I didn't know about the record. The ball was swinging from the very start and to get the wicket with the first ball made me very happy.
We are capable of doing better than this, but the batting is just not working
Bangladesh captain Khaled Mashud
"On the hat-trick ball, I wasn't really feeling anything. I just wanted to make sure I put the ball in the right place."
In fact, Vaas said he had not begun the game in positive mood.
"I woke up this morning and my back was very sore," he said.
"I came in and saw the physiotherapist Alex (Kontouri) for treatment and it was still sore. But when I came in to bowl it started feeling better."
Jayasuriya also made a sizeable contribution to his side's ten-wicket win, as he and Marvan Atapattu overhauled the target of 124 with 27 overs to spare.
However, that meant that the Sri Lanka middle order missed out on valuable batting practice with tougher games against West Indies and South Africa still to come.
"Perhaps in future games we might have to think about changing the order," said Jayasuriya.
"But we can't take things lightly - we want to win all the games we possibly can because it's better in the long run."