The Sri Lankans barely had any chinks in their armour © Getty Images

If Bangladesh's audacious win against India last weekend provided a glimpse of their brave new world, a future that is looking increasingly exciting, their outing against Sri Lanka was a flashback to their darkest losing days. Bangladesh were treaded on early and then ruthlessly trampled upon by a Sri Lanka team looking serious title contenders after their second outing.

The verve that Bangladesh displayed against India had all but erased their minnow status and Sri Lanka's captain, Mahela Jayawardene, insisted that they would be giving full respect to their Asian brethren. True to his words, Sri Lanka produced a cohesive, skilful and intense team effort that overpowered Bangladesh.

It was a crucial game for Sri Lanka, a potential banana-skin that could easily have derailed their World Cup, but by winning today they filled themselves with confidence, gathered precious momentum, and all but confirmed their place in the Super Eights. India, desperate to win on Friday in their do-or-die clash, will have to be at their very best if Sri Lanka turn-up in the same mood.

The tone of the match was set early by Sanath Jayasuriya, the old journeyman that is still their biggest matchwinner in ODIs. Bangladesh's decision to bowl first was not unexpected and there was also the anticipated early movement for the new ball. But Jayasuriya is a master at upsetting the rhythm of bowlers and after a watchful start he snatched the initiative with a couple of trademark swipes.

Thereafter, until struck down by leg cramps, Jayasuriya motored along in prime form. Upul Tharanga (26) gave decent support in a 98-run stand and Jayawardene (46), the least convincing of the top order, also played a useful hand. Kumar Sangakkara was in good form and strode effortlessly to a fifty, while Chamara Silva once again impressed with an electric finish full of stylish strokes, especially an astonishing one-legged flick for six from a delivery that pitched outside off stump.

While the batsmen, especially the openers, laid the foundation for the victory, Sri Lanka's bowling attack once again looked the most well-balanced in the tournament. Chaminda Vaas produced a mini swing bowling masterclass and Lasith Malinga was too sharp for both Tamin Iqbal and Aftab Ahmed. By the time Muttiah Muralitharan entered the attack, the result was foregone.

The wide margin of victory now means that Bangladesh must rely on Sri Lanka to qualify. If all three teams are on equal points then Bangladesh, in all probability, will not make the cut. But if Sri Lanka maintain their best form in Friday's high-pressure game and India lose then Bangladesh will sail through to the next round.

Charlie Austin is Cricinfo's Sri Lankan correspondent