New British record for Richards in Fukuoka

The Mixed 4x100m Medley quartet of Medi Harris, James Wilby, Jacob Peters and Anna Hopkin, meanwhile, placed fifth in the world as they looked to secure a Paris 2024 spot in that event for GB, while Freya Anderson was seventh in the final of the Women's 200m Freestyle.

The standout British swim of day four came early in the session, as Richards lowered the British record in the Men's 100m Freestyle for a second time in the day to qualify fastest for the World Championship final in Fukuoka.

The newly-crowned 200m Freestyle world champion clocked a 47.59 in the morning's heats to become the fastest British man ever over two lengths of the pool - and he was in even more impressive form in the semi-final, showing the same perfect pacing from Tuesday night to finish strongly and touch ahead of Australia's Kyle Chalmers in a time of 47.47, securing lane four as he goes in search of a historic 100m-200m Freestyle double. 

Reflecting on two professional displays on the day and securing the new best-ever GB time, Matt said: "Coming into this today, it was all about progressing through the rounds, trying to swim smart - that was what got us the win last night, being smart with how we raced it.

"So that's what it's been about in both of those, getting the job done to get a place for tomorrow. Getting lane four is great, it should be a really good race, it's another stacked field - I'm just really excited to get going again. 

"Something we really prepared for was trying to be as stable emotionally as possible after the win in the 200m Freestyle, to allow us to have as much energy as possible to again in this 100m. And likewise, regardless of the outcome tomorrow, good or bad, the same will stand - we'll try to stay as emotionally stable as we can to get ready for the relays at the back-end of the week." 

The session was closed with the mixed medley relay, an always-popular event in which Britain remain Olympic champions and world-record holders from Tokyo 2020. 

Harris, Wilby, Peters and Hopkin swam both the heats and final on the day, dropping time in the final to place fifth overall and clock a time that they will hope can secure an Olympic berth in 12 months time. 

"This exact team swam in the Europeans last year, we had a lot of fun doing that, we were all very tired after the back-to-back meets we'd had last summer," said Wilby after the race.

"So doing it again this year helps to refine little things, even if it's just as simple as how each other go into the wall as we do takeovers, because whatever the team looks like next year, that could be really important potentially for relay alternates if it comes to that. 

"Everything like that really matters when it comes to trying to win big medals. We are here doing a job this year, we're ticking boxes for the bigger team, and that's hopefully done this time."

In the Men's 200m Individual Medley, there will be two Brits in Thursday's final as Duncan Scott and Tom Dean both secured lanes. 

Scott, fastest in the morning heats, is the second-quickest into the final after his usual dominant finish on the freestyle leg, the six-time Olympic medallist staying in touch over the opening 100m and pulling back on some rivals down the breaststroke lap before the pacey freestyle. 

And after missing out on last year's Worlds after illness, Duncan is relishing being back in a global showpiece. 

"There are a lot of the boys in there I've not raced before, missing last year, so it's good to get in there and race them ahead of next year in Paris. That's the main reason why I'm looking forward to tomorrow night, it's why I wanted a good lane as well, really just to get a sense of what it's like," he said.

"I'm really happy I moved it on and see where I can make some changes ahead of tomorrow. Deano has already had a great week, Marchand speaks for himself, Carson is swimming well, Seto - it's going to be pretty good fun, so I'm looking forward to it."

Scott raced in the second semi-final, with Dean having done his work in the opening semi to ultimately qualify seventh. Like Scott, two-time Olympic gold medallist Dean - who took silver in Tuesday's 200m Freestyle finale, behind Richards - finished fiercely on the freestyle to get the job done after finding himself with some distance to make up, ultimately qualifying seventh. 

Laura Stephens looked in great form as she qualified for the final of the Women's 200m Butterfly. In both her heats and semi-final swims, the David Hemmings-coached butterfly specialist took the race out well to lead at 150m, holding on down the home straight to complete a pair of composed swims. 

Qualifying sixth overall into the world final, Stephens feels she is in a good place to move things on again when it really matters.

"I'm really happy with that. Both swims were really solid today, so I'm just going to build on that into tomorrow, and hopefully I can put something really fast together tomorrow night," she said.

"This is my third World Champs now, so I do feel like I'm a lot more experienced and a lot more relaxed than I ever was before. I'm just trying to use that as much as I can as I go through the rounds, and I'm really excited for the final!"

In the second semi-final, Emily Large just missed out on the final with Laura, placing 10th overall at her maiden World Championships.

Lauren Cox, another World Championship debutant, booked herself a first global final spot after a brilliant personal best saw her qualify third-fastest in the Women's 50m Backstroke.

Having just missed out on the 100m Backstroke final, Lauren showed her sprinting qualities, getting out early over the one-lap race and holding her pace to the wall, touching in 27.29 to smash her previous best, with her parents in the Marine Messe Fukuoka Hall A stands.

"I'm really, really happy. It's good to have one of the middle lanes and be in the mix with the big girls, it's cool. Hopefully I can go again tomorrow and see if I can drop the time down some more," she said.

"It's amazing out there, the crowd is really good and my parents are here, so it's nice to see them waving the flag. It's really nice to perform in front of such a big crowd."

Freya Anderson set a new personal best to make the final of the Women's 200m Freestyle - and she was part of a world-record race to kickstart British involvement for the night.

Anderson looked to stay with the leaders early on in an opening 100m under world-record pace, building towards her strong finish. Ultimately, the Bath Performance Centre athlete placed seventh in a contest that saw Federica Pellegrini's 14-year-old world best time downed. Anderson's time was just down on her 1:55.85 semi-final swim, but she feels in a good place ahead of the Women's 4x200m Freestyle Relay tomorrow (Thursday). 

"It wasn't the race I wanted. But to make the final was one of my goals coming in. I'm really disappointed I couldn't build on my semis time, but it was an amazing race to be in that field - definitely an experience," she said. 

"My individuals are done, so I'm now looking forward to doing the relays with the girls again."

Earlier in the day, Lewis Burras missed out on the semi-finals of the Men's 100m Freestyle, the 2022 Worlds finalist placing 31st overall.

HOW TO WATCH, LISTEN AND FOLLOW

• Live online broadcast coverage of every session is available via the All Aquatics platform (or the World Aquatics Recast Channel).
• You can listen to live radio commentary of all the finals on BBC Radio 5Live, 5Live Sports Extra and BBC Sounds.
• Meanwhile, our 'What's On?' page provides links to schedules, results and more