They kick off the global showpiece in Geelong against a Namibian team looking to spring another surprise after making the Super 12 stage on their tournament debut last year.
Originally scheduled to take place in 2020 before being moved because of Covid, the eighth edition of the event begins with a double-header at the 36,000 capacity Kardinia Park outside Melbourne.
Later on Sunday, the United Arab Emirates face the Netherlands, before two-time champions the West Indies, Scotland, Zimbabwe and Ireland join the fray in Hobart on Monday.
Despite 2014 champions Sri Lanka failing to automatically qualify for the Super 12, skipper Dasun Shanaka believes they can go far after beating India and Pakistan on their way to winning the Asia Cup last month.
“The momentum is there and winning the Asia Cup really helps going ahead to the World Cup,” he said.
“Qualifiers will really help because we will play in the conditions before the main tournament happens, so it will be good for us.”
They must first get past an experienced Namibia led by Gerhard Erasmus, who is hoping for more big performances from talisman David Wiese and paceman Ruben Trumpelmann, both of whom played key roles last year.
The Africans also played Sri Lanka first up in 2021, crashing by seven wickets, before beating the Netherlands and Ireland to qualify from the first round.
The eight teams in the first round are chasing four places in the Super 12, which gets under way on October 22 when defending champions Australia take on beaten 2021 finalists New Zealand in Sydney.
England, South Africa, India, Pakistan, Bangladesh and Afghanistan will also be waiting.
The top four progress to the semi-finals before the final at Melbourne Cricket Ground on November 13.
Like Namibia, the UAE are playing only their second T20 World Cup and come into the competition on the back of two defeats to Bangladesh.
They last featured in 2014 and suffered three convincing losses, with any victory this year historic.
Ryan Cook’s Netherlands, who the UAE face first, are in their fourth successive World Cup but angling for a first win in the competition since 2016.
“We will look to continue the progression that was evident through the summer into the tournament,” said Cook, whose team swept through July’s qualifying tournament to seal a World Cup spot.
The West Indies are the event’s only two-time champions, but like Sri Lanka must play the first round. They are paired with Scotland, Ireland and Zimbabwe.
Nicholas Pooran’s men, who lost twice to Australia last week, face Scotland first in Hobart on Monday with Ireland and Zimbabwe also meeting in the Tasmanian state capital.
“We are getting accustomed to the conditions, putting our ego aside and working on the team plans,” said Pooran.
Once the qualifying is completed, Aaron Finch’s Australia will look to create history as the first back-to-back world champions when they get under way against Kane Williamson’s New Zealand.
England face Afghanistan in Perth on the same day.
A blockbuster clash follows 24 hours later in Melbourne when India, missing injured pace spearhead Jasprit Bumrah, meet arch-rivals and 2009 champions Pakistan, with more than 90,000 fans expected.