Sri Lanka can become the first team to seal a World Cup quarterfinal slot on Thursday and virtually ensure last eight spots for New Zealand and Pakistan at the same time.
A win against Zimbabwe in Pallekele would take the co-hosts to the top of Group A with seven points, ahead of New Zealand and Pakistan, who both have six.
Vice-captain Mahela Jayawardene said the 1996 champions were yet to peak but believes their campaign has been energised by Lasith Malinga's belated entry after the slingshot seamer missed the matches against Canada and Pakistan with a back injury.
"Lasith coming back into the team has given us a few more options in our bowling attack which is great," said Jayawardene of Malinga, who took a career-best 6-38 against Kenya.
Malinga also took his second World Cup hat-trick during that match.
"I think we can still improve on our batting, try to bat for longer periods and make sure we build partnerships. Even on the field there is always room to improve.
Jayawardene also warned his team not to underestimate Zimbabwe, who still has an outside chance of making the last eight.
Sri Lanka face a potentially tough last match against New Zealand in Mumbai so they can ill afford any upsets against the African nation.
"We rank Zimbabwe with any other team. I think they are a very good all-round side and we know they can be a surprise package so we are not taking anything lightly," said Jayawardene.
Zimbabwe captain Elton Chigumbura, whose team are in fifth spot in Group A with two points, said his team would take inspiration from giant-killers Ireland, who upset England by three wickets in a Group B match last week.
"My team has been on that path. If you believe you can beat a bigger team, you can do that. It's up to every individual to have that same belief and that gives me motivation."
Zimbabwe have played three times so far - losing heavily to Australia and New Zealand but beating Canada by 175 runs.
There are still 17 matches to go in the group stages of the World Cup but barring a major upset, it looks likely that the top eight sides in the world rankings will all make it through to the quarter-finals.
Unbeaten India, who top Group B with seven points, are virtually certain of their place after labouring to a five-wicket win over the Netherlands in New Delhi on Wednesday.
But skipper Mahendra Singh Dhoni said the pressure they faced after being 99-4 at one stage chasing a modest total of 189, would stand them in good stead for tougher challenges ahead.
"It's a good experience to have because you're all of a sudden in the quarter-finals or against a stronger side," he added.
"You don't want your middle order, your lower middle order, to get exposed. It's good that most of the batsmen have got a decent hit in the games they have played."
Dhoni said it was important for the team to pick up momentum with matches against South Africa and the West Indies to come before the quarterfinals.