Russian Yelena Isinbayeva defended her pole vault crown with a leap of 4.80m at the World Championships but failed to break her own world record of 5.01m.
Isinbayeva has only been beaten three times in the last three years
Kenya's Janeth Jepkosgei, title favourite for the women's 800m, also notched up a dominant win, leading the field from start to finish in Japan.
In a day low on British participation, a gutsy run from Tasha Danvers-Smith saw her reach the 400m hurdles final.
Tim Benjamin was also back to form as he qualified for the 400m semi-finals.
Isinbayeva was the only athlete to clear 4.80m, after spending the first three rounds lying down with her head under a towel.
But the 25-year-old failed all three attempts to raise her own world record 1cm up to 5.02m.
Isinbayeva has totally remodelled her technique after changing coaches to Vitaly Petrov, the former coach of the male world-record holder Sergei Bubka.
"It means so much to me because it's the first big medal since I changed techniques," Isinbayeva told BBC Sport.
"Sometime after 4.80m I get tired quickly and maybe if some girls could go to 4.80m, maybe I could stay focused."
Physically and mentally the 100m drained a lot out of me - I am just trying to refocus
Czech Katerina Badurova took silver with 4.75m and Russia's Svetlana Feofanova bronze after taking an extra vault to clear the same height.
Jepkosgei went out at a gruelling pace in the 800m and had built up a five-metre lead at the bell.
Three-times champion Maria Mutola was among those to struggle with the pace and she stopped 70m from the finish, leaving Hasna Benhassi to pick up silver and Mayte Martinez the bronze.
"I didn't want to set the pace too slow because I knew everyone was waiting for me," said Jepkosgei, 23.
"I had to take a risk and I did it. I'm happy and I hope to do it again."
Danvers-Smith slashed her season's best by more than a second to reach Thursday's 400m hurdles final behind Australia's Jana Rawlinson in 54.08 seconds.
The 29-year-old is close to the personal best she set in 2003 before the birth of her son Jaden.
"I am building myself back up to where I was and where I could have been," said Danvers-Smith, who was sidelined by an Achilles injury earlier this year.
Welshman Benjamin rediscovered some form to book his place in Wednesday's semis with a time of 45.44 seconds.
"It's not my goal achieved," said Benjamin. "If I can go under 45 seconds and get into the final, that's great."
Benjamin coped well from lane one in the hot conditions
Team-mates Martyn Rooney (45.47) and Andrew Steele (45.54) failed to advance with Rooney missing out on a fastest losers' spot by 0.3 of a second.
Benjamin's build-up to the Worlds was hampered by an ankle injury and his training was also affected when he split from coach Colin Jackson last month.
"I have had a poor preparation," said Benjamin. "I made some coaching decisions that just didn't work out and also because of injury so hopefully I can put that behind me.
"The competition this year is the toughest championships I have been in by far. I'm going to have to go all out in the semi-final, that time is not going to get me through."
American LaShawn Merritt was the fastest man through to the next round in 44.78, while defending champion Jeremy Wariner eased through in 45.10.
"I shut it down at 250m. So, you'll see about it on Wednesday," he said. "I'm ready to go in the semis. The track is so fast."
Tyson Gay stayed on track for the sprint double by qualifying for Wednesday's 200m semi-finals.
Jamaican Usain Bolt also looked very impressive as he went through along with Gay's American team-mates Wallace Spearmon and Rodney Martin.
"I'm gritting my teeth," said Gay, the American 100m champion, who was the fastest qualifier in 20.08 seconds.
"Usain Bolt made me run a bit faster than I wanted to run, but I just wanted to get through as easy as possible.
"Physically and mentally the 100m drained a lot out of me. I am just trying to refocus."
Ireland's Paul Hession, who won the final heat, told BBC Sport: "I have to believe I can make the final."
Tirunesh Dibaba has shelved her plans to defend her 5,000m title because of stomach cramps.
The Ethiopian successfully claimed a second 10,000m crown on Saturday but withdrew from Wednesday's 5,000m heats.
"It really bothered me in the 10,000m. The stomach cramps are very painful but I have had them on and off since last year's World Cross Country Championships," said Dibaba before making her decision.
Frenchman Mehdi Baala's charge through the field in the 1500m semi-final has resulted in a bumper line up for the final.
The 2003 world silver medallist was disqualified after sending Youssef Baba of Morocco and Spaniard Juan Carlos Higuero crashing to the ground on his way to fourth place in Monday's first semi.
New Zealander Nick Willis, who finished sixth in the heat, qualified in place of twice European champion Baala, while Baba and Higuero were put through as the 13th and 14th finalists.