The madness continued on days three and four at the IAAF World U20 Championships in Tampere, with youth beating experience and a deluge of shocks flooding the favourites. Here are some of the highlights. 

Sweet Sixteen

Briana Williams ()

Sixteen years, 113 days – that's how long Briana Williams had been alive when she settled into the blocks for the women's 100m final on Thursday night. 

It's also three years and 56 days less than Twanisha Terry, the US sprinter who most seasoned experts predicted was a lock for the gold medal, especially after she blitzed her semi-final in 11.03. 

And yet, and yet...

Williams lined up knowing that she had one major edge over Terry – her start – and it was a weapon her coach, Ato Boldon, told her she needed to utilise to good effect. 

"We knew that she’d most likely be in the lead at 50 metres,” he said. “I told her before the race that if she panics, then the others will go past her, but if she holds her form, she can win it.”

That she did, exploding from the blocks, holding her form in a way most 26-year-old elite athletes could only dream of, and reaching the line in a mind-boggling 11.16, good enough for gold. 

Jamaica hasn't had the best run of things at senior level recently, the murmurings of a decline in their sprint super-powers growing louder with each week, but in one fell 11-second swoop on Thursday, Williams silenced the lot of them. 

Kids today, eh?

Who's the Manangoi?

George Manangoi ()

All hail King George. 

George Manangoi, that is, the world U18 1500m champion, world U20 1500m champion, younger brother to world 1500m champion Elijah, a 17-year-old with a sick turn of speed, a strong reserve of stamina and a savvy sense for championship racing. 

He needed all of those on Thursday night to defeat what was, in our admittedly feeble memory, the best middle distance field ever assembled at the IAAF World U20 Championships. 

To win, Manangoi had to absorb a flurry of punches from middle-distance heavyweights and then, somehow, dig deep within himself to land his own haymaker. 

The first move came from Samuel Tefera of Ethiopia, the world indoor 1500m champ, who went hard from two laps out and tried to turn everyone's legs to sludge. Then came Kenya's Justus Soget, a 3:32 chap who hit the front turning for home, and then, THEN, arrived Norwegian wunderkind Jakob Ingebrigtsen, taking the lead with 40 metres to run and looking set for gold. 

But Manangoi watched all that happen from behind, then turned over the equivalent of a royal flush, surging to the lead as the line approached to win in 3:41.71. 

It meant the world U18, U20 and senior men's 1500m titles now all belong to the same family.

Any room left on that mantelpiece?

A star is born

Jonathan Sacoor wins the 400m at the IAAF World U20 Championships Tampere 2018 (Getty Images)

Hands up if you knew much about Jonathan Sacoor last week? If so, top marks to you, but for most of the athletics world, this rising star only went supernova on Friday night. 

On a damp track in Tampere, the smooth-striding 18-year-old made a name for himself, and made sure it's one the world won't forget in a hurry. 

Up against sub-45 man Christopher Taylor, Sacoor, who wasn't even ranked in the top 10 coming into the event, shook up the world with a phenomenal victory in 45.03, Taylor fading close to home and finishing second in 45.38. 

"Going into the race, I didn't think it was possible for me to win,” he said. 

Neither did we, but there you have it. 

Great Britons

Niamh Emerson ()

London 2012 had Super Saturday, but for British people Tampere 2018 had Fab Friday – a magical couple of hours where they scooped three gold medals. 

First, there was Niamh Emerson, who crowned off a heroic heptathlon with a fearless 800m, where she went for it despite the presence of Austria's Sarah Lagger in her slipstream. Splashing through the rain on a track that was more of a river, she came home in an astonishing 2:09.74. She needed to lose to Lagger by less than 0.14 to win gold, instead she beat her by two seconds. 

Shortly before, her teammate Jake Norris whacked his national U20 record for six by chucking the hammer 80.65m to defeat Ukraine's Myhaylo Kokhan. 

After that, Jona Efoloko lined up for the 200m knowing most thought the gold was headed to one of the US sprinters, but he ripped up the script and re-wrote himself as the new lead, taking gold in a lifetime best of 20.48.

Incredibly, it means the wait for a US gold medal goes on, four days... and counting. 

Day of the Underdog

Lea-Jasmin Riecke, the long jump winner at the IAAF World U20 Championships Tampere 2018 (Getty Images)

Coming to Tampere, Lea-Jasmin Riecke had a very simple goal for the long jump: top eight. 

The German managed that, alright, then went seven places better, unleashing a lifetime best by 14cm to take gold in the final with 6.51m.

US favourite Tara Davis couldn't produce her best and had to settle for third, while Japan's Ayaka Kora – who had the best manners of any athlete this week, bowing to officials each time she exited the pit – took silver with 6.37m. 

"I still don't believe I'm the champion," said Riecke. 

She wasn't alone.

Tears of Joy

Amálie ŠVÁBÍKOVÁ ()

It was a torrent, a wonderfully gushing flood of tears that came washing down the face of Czech Republic's Amalie Svabikova on Thursday night as she produced the finest series of her life to take gold in the women's pole vault. 

She had that sealed at 4.40m, but rather than be content with it she instructed officials to hoist that bar up to 4.51m, a PB, which she duly sailed over in what was a celebration jump. 

And it clearly meant an awful lot to her, as it should.

"I still don't believe it, today was so good," she said. 

It was her day, and no matter where her wonderfully flourishing career goes from here, she'll always have this. 

Tears of Pain

Saga Andersson ()

When you've pole vaulted 4.42m, and a mark well below that – 4.35m – will win you a medal, it's understandable that you'd be more than miffed to miss out, particularly when competing on home turf. 

But sport cares little for the narrative you want, only dishing up the one you're going to get, like a rude, non-negotiable lunchlady at school. 

In the women's pole vault final, held in damp, difficult conditions, Finland's Saga Andersson bowed out after three failures at 4.25m, and the tears began to flow afterwards for the 18-year-old, knowing a medal was there for the taking. 

Sport can be cruel at times, but in the end every wound heals, and if anything the callous created only makes for a stronger athlete next time around. 

Queen Ches

Celliphine Chespol wins the 3000m steeplechase at the IAAF World U20 Championships Tampere 2018 (Getty Images)

There is good, and then there is winning-gold-in-a-championship-record-off-a-slow-pace-on-a-wet-track good. 

Celliphine Chespol is the latter. 

There may not be a more dominant winner in Tampere all week than the 19-year-old, who doesn't so much hit the ground with her feet as caress it, who floats more than fights as she dispatches world-class rivals like they're weekend hobbyjoggers. 

Chespol, of course, is the second fastest steeplechaser of all time, though pitched into world-class company here in Tampere she could easily have come undone like so many other favourites. 

But she didn't. Instead she retained her title by swooping to the front off a slow early pace, squeezing down on rivals Peruth Chemutai and Winfred Yavi like a python, and killing them off with a 2:57 last kilometre, never a hint of pain or struggle etched across her serene expression. 

This was steeplechasing at its finest, and not so much the arrival of a new star as the coronation of one of the greats. 

Words: Cathal Dennehy