Karthik Meiyappan lit up the Twenty20 World Cup with a hat-trick Tuesday but it was in vain as Sri Lanka dismissed the United Arab Emirates for just 73 to get their campaign back on track.

The Asian champions were stunned by Namibia in the tournament's opening game on Sunday, a crushing 55-run defeat that left no room for error against the UAE.

They responded with a convincing 79-run victory, but not before some drama.

Sri Lanka were cruising at 117-2 at Geelong when spin bowler Meiyappan derailed their plans in the 15th over, removing Bhanuka Rajapaksa, Charith Asalanka and skipper Dasun Shanaka in successive balls.

It was only the fifth hat-trick at a T20 World Cup, and the first-ever for the UAE in any T20 international.

Shanaka's team recovered to post 152-8 with Pathum Nissanka making a gritty 74 and Meiyappan ending with 3-19.

It leaves Group A finely poised in the race to make the Super 12 stage heading into the third and final matches on Thursday where net run rate could prove decisive.

Sri Lanka, the 2014 champions, face the unbeaten Netherlands next, needing another win, while Namibia take on the winless UAE.

After being put into bat, Sri Lanka made a strong start, reaching 42 before Kusal Mendis was trapped lbw by Aryan Lakra on 18.

Nissanka was joined by Dhananjaya de Silva and with the trumpets blowing from the Sri Lankan fans, they both crunched big sixes.

But their 50-run partnership came to an end with an amateurish runout. Nissanka drove the ball and De Silva set off, but his partner didn't respond, leaving him stranded.

Nissanka brought up his eighth T20 half-century with a cover shot but then watched as Rajapaksa, Asalanka and Shanaka all fell to Meiyappan.

Wanindu Hasaranga de Silva was then snared by Aayan Afzal Khan four balls later as they lost four wickets for three runs.

Nissanka kept calm at the other end and began swinging his bat, before being dismissed in the final over.

Dushmantha Chameera quickly rattled UAE in their reply, clean bowling Muhammad Waseem and Aryan Lakra in the space of five balls.

The UAE had no answer to the pace attack, slumping to 21-4 in the sixth over and they never recovered as Sri Lanka ran riot. Chameera ended with 3-15 but in worry for Sri Lanka hobbled off late in the game.