There was a double triumph for Sweden in the pole vault when Angelica Bengtsson who dominated the event and Michaela Meijer trumped the opposition.
Bengtsson was a revelation coming into the final with best-ever vault of 4.12m and delighting the capacity crowd with a huge world leader of 4.32 before three failures at 4.37.
"I came to win the gold," she said on a day of double celebrations. "Now I am world champion and overjoyed. This is the best birthday present because I turned 16 three days ago."
Meijer who preceded her as world leader was not in the same shape which saw her clear 4.18 in late May, but can only blame herself when having passed 4.15, she failed with the bar five centimetres higher.
Russia's Tatyana Stetsyuk and Hungary's Felicia Horvath with personal bests shared the bronze medal with Morgann Leleux who also cleared 4.00, losing out on count back.
Another first for Sweden
Johan Rogestedt in a nail biting finish wrecked what looked to be an inevitable Kenyan 800m one-two when opening his lanky legs to slip past Peter Langat Kiplangat and Nicholas Kipkoech inches from the finish line.
Until then it seemed the gold medal was destined to stay in Kenyan hands as the pair powered down the home straight until the timely, if unexpected, intervention of the giant Swede.
Rogestedt who came into the race with a PB of 1:51.11 caused the biggest surprise of the championships in the last event of the fourth day with his unbelievable win in 1:50.92.
"This is a great surprise to be a world champion and beat the Africans," admitted the Swede. "My goal was to be in the finals."
The Kenyan pair both 1:47 perfomers, too busy glancing at each as they sprinted the final 50m, somehow didn't notice his bigger frame as he accelerated past them giving neither the opportunity to respond.
Rogestedt won by a narrow margin of just 0.05sec from Kiplangat while Kipkoech had to settle for third in 1:51.01.
Two golds for Great Britain too
Ben Williams wasn't deterred in his gold medal ambitions when with his opening jump in the triple jump he almost breeched the 16 metres only to have it adjudged as a very close foul.
The Briton didn't hold back and try for a safety clearance with his second attempt - instead he flew down the runway, hit the board perfectly and with the best leap of his life, flew out to a distance of 15.91.
That superb PB by 19 centimetres proved to be the winner although the fourth ranked hop, step and jumper in the world this year, also produced another excellent effort of 15.88 in the next round.
Behind him there was a lively contest for second place and eventually it was claimed by Supanara Suksawasti Na Ayutaya who had led the qualification with a PB 15.54.
The 17-year-old Thai unheard of until lifting the long jump title two days earlier may have been denied a double, but once again he produced the best jump of his career of 15.70.
That clearance in the second round marked him out as the likeliest challenger to spoil Williams’ day, but after a third effort of 14.83, he ended with three no jumps.
Russia's Aleksandr Yurchenko having moved into bronze medal position with 15.66 in round five ahead of Trinidad's Elton Walcott, repeated that distance, joining Williams and S.N.A. by celebrating not only winning a medal but earning a lifetime best.
Thompson supreme in Heptathlon
Katarina Thompson after leading throughout the heptathlon competition kept her cool in the final two events to become Great Britain's third gold medallist of the championships.
Thompson's success clearly suggests if her natural progression continues, she can follow in the footsteps of her fellow countrywoman Denis Lewis, Kelly Sotherton and Jessica Ennis, all world class multi-eventers.
The pressure was on Thompson when the javelin, one of her weaker events, got underway in the final session and she needed no reminding that Ennis a favourite to win the World senior title in Berlin next month, blew her chances when a youth six years ago in Sherbrooke.
Ennis led at that stage of the competition but a ghastly effort of 25.52m the worst distance of all the competitors was a setback which saw her drift backwards to fifth position.
Thompson rose brilliantly to the occasion throwing the spear to new lifetime bests of 32.61 and then with her third and final attempt to 33.77.
That saw Thompson who lives in the football stronghold of Liverpool, raise her tally to 4928 points with Laura Ikauniece who made a two metres improvement to 42.53, moving into silver medal position with 4836pts while German Kira Biesenbach who threw 29.73, dropped to third.
That meant unless there was a disaster in the final event, Thompson the fastest the 800m runner in the field, was assured of a fully deserved victory.
She sensibly to avoid any problems by staying out of trouble, immediately led and it was only in the last few strides that Switzerland's Eloide Jakob slipped past to win by 0.21sec when setting a PB of 2:19.91 with Laura Ikauniece third in 2:20.94.
Thompson who achieved five personal bests and the furthest ever by a Brit multi eventer in her age group, finished with a massive score of 5750 points.
That decimated the previous year's world leader belonging to Hungary's Xenia Krizsan of 5428 and who herself finished fourth with a tally of 5353.
Both Ikauniece and Biesenach fully deserving their silver and bronze medasls, also made huge improvements with scores of 5647 and 5423pts.
Another Sotomayor on top of podium
Norge Sotomayor won Cuba's first medal of the championships with a dominant 400 Hurdles display of front running which earned him a world leading mark for the year of 51.30.
Sotomayor (no relation to legendary high jumper Javier Sotomayor) with his flowing hurdling technique, continued where he had left off after posting the quickest mark in the semi final.
Not once did he falter even when Jose Reynaldo Bencosme De Leon and Jeremiah Mutai desperately tried clawing him back and looked like they might do it halfway down the home straight.
Sotomayor remained calm coming off the final hurdle to dash across the line 0.15scc ahead of Mutai, who finding a little strength, edged ahead of De Leon.
The Italian bronze medallist who was born in the Dominican Republic and moved to Italy in 2004 and who came to the Sud Tyrol as world leader, finished in 51.74.
"It was great to set a new world youth lead," said Sotomayor, whose idol is Olympic 110m hurdles champion and world record holder Dayron Robles.
"I have been training for a month at a camp in Havana to prepare and gold was always my dream."
Count back needed to determine High Jump winner
Israel's Dmitriy Kroyter in a tense encounter won the high jump title on count back ahead of Janick Klausen both men clearing a height of 2.20.
Kroyter a 2.28 jumper and second in this year's world list, had a lucky escape as his Danish rival lifted himself when it mattered most and improved his lifetime best by seven centimetres.
The winner who entered the contest at 2.13, kept a clean sheet through 2.17 and 2.20 before finding 2.22 to tough a target.
Klausen came in at the opening height of 1.90, kept a clean sheet until failing twice at 2.13 and again at 2.17, but with his last attempt got over 2.20 for a fully deserved medal.
Danill Tsyplakov of Russia and Canada's Django Lovett, also producing their best ever performances of 2.17, shared the brone medal.
Gold after silver for Crouser
Ryan Crouser after having to settle for a silver in the discus returned to the compact Bressanone stadium to clinch the shot put gold medal with a championship record of 21.56.
Crouser whose first effort was a no throw, went into the lead with his next effort of 20.52 and remained unchallenged with an excellent series of puts (20.55, 21.05, the winning 21.56, 21.08) for a memorable victory.
The first American boy ever to win the gold medal, he erased the six-year-old championship record which Feng Liu won with a throw of 21.45 in Sherbrooke.
Crouser who improved his PB by a single centimetre, was never under any pressure, Krzysztof Brzozowski producing his furthest and PB of 20.89 in the last round with South Africa's Frans Schutte
whose first two efforts were his only valid attempts, throwing a PB 20.37.
Kenyan girl wins 1500
Nelly Chebet Ngeiywo maintained the continuity of Kenya's hold on the 1500 gold medal when becoming the third successive winner in a time of 4:12.76.
Ngeiywo who peaked perfectly for the championships lowering her personal best to 4:17.10 in her qualifier from a previous fastest of 4:22.1 at altitude in her homeland, had much more speed over the final circuit than Gete Dima and Amela Terzic.
Her pace down the backstraight and off the final bend, pulled her well clear of Dima the Ethiopian clocking 4:15.16.
Terzic from Serbia and ranked third in the world before coming to the meeting, produced a personal best finishing in 4:16.71.
Merima Mohammed who was in a pack alongside the trio who were bunched together at the bell was unfortunate to trip 50m afterwards and lost her chance of medalling.
"I was never worried about winning this race," said Ngeiywo a close friend of Pamela Jelimo the Olympic 800m gold medallist.
Ngeiywo who has six brothers and four sisters, revealed: "I train with her, but it is really tough because she is so fast."
Russian upsets Jamaicans in Hurdles
Danielle Dowie and Ristananna Tracey seemed to have bagged the 400 hurdle gold and silver medals until there was drama and tragedy as the powered down the home straight.
The Jamaican pair fighting a domestic battle, weren't aware world leader Vera Rudakova was tracking them down and the Russian's finishing speed caused Tracey to panic.
Rudakova hit the final hurdle almost in tandem with the Caribbean duo and Tracey reacted by losing control and falling to the ground although getting up and finishing last.
Dowie had no pace in her legs as Rudakova who ran 57.83 in the qualifiers three days earlier, exactly matched that world lead.
Dowie crossed the line in 58.62 with Deborah Rodriguez winning Urugay's first medal in a time of 59.71.
Chinese takes discus gold
Shanshan Li with an opening discus effort of 51.65 won with that distance although during the competition also producing four other throws over 50 metres and ending with a foul.
Li's consistency totally overshadowed the display of the American Alex Collatz who set the world leader of 53.95 in early June, although it was always expected it would be a close encounter as Li's PB is 53.20.
But the battle failed to occur and Collatz with only one 50-plus throw had to settle for the silver medal with a second round effort of 50.09.
Germany's Shanice Craft at her best a 50.57 performer and with Collatz below par had a good opportunity of a higher placing, failed to grab the chance and placed third with a throw of 49.15.
While Javelin goes to Ukbekistan
Cuba's Lismania Munoz led after first round 49.85 but by the third round found herself relegated to seventh position in a high quality competition.
Anastasiya Svechnikova of Uzbekistan lived up to her reputation and after coming to the championships with 56.14 personal best to her credit, and duly took the gold medal.
Svechnikova's winning throw of 53.25 came in the second round and showing consistency she also produced lengthy throws of 52.81 and 53.22 to dominate the competition.
Indeed runner-up You Wun's best effort was well below Svechnikova's three efforts but her furthest of 52.04 in round five, saw the Chinese girl's PB and snatch the silver medal from Laura Henkel.
Henkel of Germany also produced a lifetime best of 51.47 in round three before Wun denied her second place.
Svechnikova who despite her age, competed at last year's Olympics, said: "I am thrilled with my win and in Beijing I ranked 35th out of 54.
Coached by her mother and her father a judo expert, she added:"After that I got injured and was out for a while."
Jodie Williams remains on schedule to become the first girl to achieve the championships sprint double but the Briton knows it isn't going to be an easy task given the form of her rivals.
American Briana Nelson set the ball rolling when running a very relaxed season's best of 23.78 while Allison Peter runner up to Williams in the 100m final, was just as impressive.
The US Virgin Islander fastest in the first round ran an immaculate bend which she came off with a good lead, to break the tape in 23.60.
Williams was also on the ball and possibly making a point to Ashton Purvis the 100m bronze medallist, ran a fast first 100m then holding the pace, beat the American by 0.56 in a time of 23.44.
Kirani James also remains on target to add to his 400 title double after cantering through his 200 semi final in a time of 21.23 - the second fastest of the day.
Dedric Dukes was a one-hundredths-of-a-second quicker in his qualifier, but the easiness in style which Grenada's James showed, suggests the American will be challenging for a minor medal.
Dukes' fellow countryman running Keenan Brock achieving a PB 21.36, should also be in the hunt with the European trio of Alberto Gavaldo (Spain), Tomasz Kluczynski (Poland) and Sam Watts (Great Britain) after good runs, also capable of making the podium.
David Martin for the IAAF