The Union Jack has flown up the flag pole to its World Championship zenith.

Seldom is there a more palpable pressure than that felt before the 4x100-metre relay finals, but both British quartets made a mockery of the nerves by collecting silver medals.

The women were first up and despite late confusion with Imani-Lara Lansiquot's withdrawal, they launched the most tangible challenge to an indomitable Jamaican team.

The destination of the gold was inevitable from the moment Shelly-Ann Fraser-Pryce tore up the back-straight, but Daryll Neita was gaining on the Caribbeans by the time the fourth leg concluded.

Key to the silver medal was an immaculate set of changeovers and although Dina Asher-Smith wasn't afforded the poetry of bringing it home, she contributed to national and personal history nonetheless.

British adoration for Asher-Smith

The 23-year-old, who also won a silver in the 100m and struck gold in the 200m, is the first British athlete in history to win three World medals at a single championship.

And in spite of Asher-Smith's subsequent blushes, the trio of Asha Philip, Ashleigh Nelson and Neita couldn't help eulogising about her in the mixed zone.

'She's putting us on the map', 'of course she's inspiring', 'she's paved the way for us' and 'she's killing it and smashing it' were just some of the compliments thrown around.

However, speaking with her characteristic class, the British superstar enthused the importance of teamwork by insisting: "This wouldn't even be a conceivable idea without the teamwork.

"At the end of the day, it's a team event. You can't do that on your own, I can't run a 400m in 41.85 seconds and I don't think anybody can. So, thank you ladies, it's great to be on a team with you."

British men make relay history

The men were unable to retain the World crown they won in London, but it took a quartet of American 'Galacticos' and the third fastest time in history to rip it away from them.

Adam Gemili was second only to the electrifying Christian Coleman out the blocks, Zharnel Hughes ran through a hamstring injury down the back-straight and Richard Kilty gave the top bend a lashing like it owed him money.

And need I say anything about Nethaneel Mitchell-Blake and a home straight? That timeless match made in heaven ensured Noah Lyles crossed the line with a gradually dwindling lead.

It was a silver medal that couldn't have been captained by anybody worthier than Kilty who - in tune with his superb leadership all week long - unabashedly sung his team's praises afterwards.

Captain Kilty leads the praise

"It took the second fastest time in history to beat us," Kilty reiterated with visible pride. "That's the best team that America have ever, ever assembled and there's still more for us to improve on.

"Zharnel pulled his hamstring, what an absolute warrior coming into his own. You know, he went through a pulled hamstring to deliver me that baton. We're so proud of each other collectively.

"We're like a family and we all came together there. You can see, that no matter what happens, we adapt. Pulled hamstring, we adapt. We know each other so well. I was blind, but I could sense something was wrong.

"No matter what, we work together like clockwork. We've got so much faith in each other and it's great to be a part of."

In the end, the British time of 37.36 seconds was the joint sixth fastest in history, quicker than the winning time in 2017 as well as a British and European record.

Hassan shines, but no medal for Muir

Laura Muir couldn't possibly have done anymore during the 1,500m final. To run one of the fastest times of her career - an eye-watering 3:55.76 - and only come fifth was the cruellest of fates.

But in the context of an injury-blighted season, Muir was still feeling very positive: "It gives me a lot of confidence to know that things can be so destructive and I can still go out and do that type of performance.

"Hopefully next year I'll be fighting fit going into the Olympics and if I can do that, then goodness knows. 3:55 is me unfit so, if I'm 100% fit, I'd love to see what I can do."

There was simply no stopping the omnipotent Sifan Hassen, who became the first woman in history to collect the 1,500m and 10,000m double at a World Championships.

Not only that, but she clocked an astonishing time of 3:51.95 to break the championship record and move to sixth on the all-time list behind Genzebe Dibaba and a quartet of Chinese athletes.

A shot put final for the ages

Hours have passed since the conclusion of the men's shot put, but we're still speechless.

Ryan Crouser opened the competition with a championship record of 22.36 metres, only for reigning champion Tom Walsh to launch an astonishing 22.90-metre throw just minutes later.

Brazil's Darlan Romani then became the third man to surpass the championship record prior to Doha 2019 - throwing 22.53 metres - but would mind-blowlingly finish short of the podium.

That's because Joe Kovacs threw the fourth(!!!) throw of the evening to make the history books, registering 22.91 metres to become the third greatest thrower in history.

Think we're finished? Well, you'd be wrong because Crouser left the Khalifa International Stadium in shock, falling just one centimetre short of the lead with the second 22.90 of the night. Astonishing.

Fourth greatest jump ever for Rojas

It speaks volumes about Saturday night's quality that Yulimar Rojas' victory in the triple jump is this far down the page.

The Venezuelan showed exactly why she's the second best jumper in history, delighting the Doha crowd with a remarkable 15.37-metre jump that demolished her opposition in one feel swoop.

That distance, the fourth farthest in history, was understandably out of grasp for eventual silver and bronze medalists Shanieka Ricketts and Caterine Ibarguen.

Electric atmosphere for 5,000m final

One common theme throughout the championship has been the appetite for middle and long distance events, so it was inevitable that the women's 5,000m final would stir up a frenzy.

Britain's Eilish McColgan, who eventually finished tenth in a personal best, set the tempo early on but the group of East Africans - broken only by Konstanze Klosterhalfen - gradually asserted their dominance.

And to the tune of an absolute tumult from the stands, Hellen Obiri romped her way to gold and it wouldn't have been tonight if it wasn't in a championship record time - clocking 14:26.72.

Respect between world-record holders

The 100m hurdles finally cracked into gear and Kendra Harrison started her campaign by qualifying third fastest in 12.55 seconds behind Danielle Williams and Tobi Amusan.

The world-record holder took to the track less than 24 hours after her compatriot Dalilah Muhammad consolidated her place in the history books with another all-time best in the 400m hurdles.

And the respect between the American legends was clear to see when Harrison told GIVEMESPORT: "Oh man, for her to break her own world record, that's gold in my book.

"Just to see that definitely gives chill-bumps. She's the best person ever in that event and she's done it twice. So, that was just amazing to see."

However, Harrison won't be joined by her fellow American Brianna McNeil in the semi-finals. The Olympic champion suffered a shock disqualification - despite her protests - for a false start.

Two out of three British jumpers progress

The female sprint-hurdlers weren't the only athletes desperate to get their Doha campaigns underway and a trio of British long-jumpers finally took to the runway tonight.

Sadly, Jazmin Sawyers couldn't progress to Sunday's climax on 6.46 metres, but Abigail Irozuru and Shara Proctor moved on with 6.70 and 6.63-metre jumps respectively. 

GIVEMESPORT caught up with Irozuru afterwards and she couldn't help laughing when I suggested that we were nearly eligible for state pensions by the time the long jump finally started.

"Oh my goodness, it's been horrible," the British champion said through a smile. "I mean, we fly back on Monday at six in the morning!

"We're here, on the other side of the world, where people can enjoy the sights and I'm like: 'oh, I can't do anything. I'm going to stay in my hotel room. I can't enjoy any of this buffet!'"

Reese blames herself for shock elimination

However, title holder Brittney Reese won't be defending her crown in Doha, bowing out of the qualifying rounds on 6.52 metres and the 2012 Olympic champion placed all the blame on herself.

Reese explained in the mixed zone: "I felt like I was running fast, but unfortunately I wasn't running fast. Two jumps behind the board, then basically almost a safety jump for my second and the third one just didn't hold up.

“It just wasn't my day today. I felt going in, everything felt like it was going in the right direction. I 100% put the blame on myself. I didn’t execute the plan, it’s totally my fault.”

One of the great nights of athletics

The stage was set for one of the greatest nights of athletics long before the relays, but how fitting that two quartets of Brits would round off an unforgettable evening with their brilliance.

Did either team have the best individual sprinters? Absolutely not, but this is the relay and teamwork absolutely makes the dream work.

Even with American and Jamaican teams beyond comprehension, there was a chemistry, as well as the baton, passing between British runners to guarantee their places in history.

The Union Jack itself is an amalgamation of four flags and when it flutters above two podiums tomorrow, it will - once again - stand for the magnificence of four entities coming together.