The two teams with the most World Cup titles and tournament favourites in this edition - defending champions Australia and hosts England - will face off in Bristol as the race for a place in the semi-finals nears a tight finish.
Australia have a chance to secure a semi-final berth with a win, while a victory could put England on top of the points table, with eight points from five games and healthier net run rate than the other teams.
If numbers are anything to go by, Australia, six-time world champions, have a clear edge over the hosts. Out of the 71 matches between the two, Australia lead England 47-20, having won 11 out of 16 matches in the World Cup. The last time they met in a World Cup, Australia upstaged England by two runs in a low-scoring thriller in Mumbai after seamer Anya Shrubsole's 3 for 24 had limited Australia to 147.
The two teams, however, haven't played in the format against each other since the 2015 Ashes. Back then Australia captain Meg Lanning scored 85 and strung an 85-run partnership for the fourth wicket with Ellyse Perry to hand the hosts an 89-run drubbing in Worcester.
The numbers could turn a shade brighter for England on Sunday if Lanning opts to sit out her second successive match. She was rested in Australia's previous game against Pakistan to avoid aggravating her chronic shoulder injury. Australia coach Matthew Mott was "very hopeful" of Lanning's return for Sunday's match, even as he praised middle-order batsmen Elyse Villani and Alyssa Healy for taking on the onus with fifties in the side's 159-run win over Pakistan.
The Bristol pitch, in the previous match, had produced a 678-run slugfest between England and South Africa. A new surface will, however, be used for Sunday's game, which could most likely facilitate the contest ending up as a battle of two unwavering batting line-ups with six centuries between them in this edition. Despite the batting-friendly nature of the track, the spinners of both teams could pose a challenge, having been the preferred mode of attack, with 37 wickets between them.
Sri Lanka and West Indies, on the other hand, will be pursuing their first wins in this edition, in Derby.
Having lost all five warm-up fixtures, followed by four consecutive defeats in the league stage, West Indies are languishing at the bottom of the table. They batted first in all four matches so far and their narrowest margin of defeat was by seven wickets against India.
After folding for 48 against South Africa, they crawled to 150 against New Zealand, and were smashed by Rachel Priest, who scored the fastest Women's World Cup fifty. New Zealand went on to beat West Indies with 190 balls to spare.
Sri Lanka will look to build on their performance against India, where they nearly pulled off a win. Medium-pacer Sripali Weerakkody, who kept India's batsmen in check with 3 for 28, said the remaining matches were a good platform for the seniors to pass on knowledge. "We have so many juniors in the team, so we can give a chance to them and do something good for the future," she said.
Both teams are matched evenly in head-to-head numbers, each having won 14 out of 28 ODIs.
Former West Indies captain Merissa Augilleira admitted the side has been far from showcasing the might that took them to the final of the 2013 World Cup. "We know our potential, we know what this team has and what we can do but apparently it is not clicking for us," she said.
While little may have gone West Indies' way so far, a look back on their previous World Cup encounter against Sri Lanka in 2013 could serve them a much-needed encouraging stimulus ahead of what is poised to be a knockout game. Led by Stafanie Taylor's unbeaten 171 and a 22-ball 50 from Deandra Dottin, West Indies had piled up 368 before consigning Sri Lanka to a 209-run defeat.
Annesha Ghosh is a sub-editor at ESPNcricinfo