Russia's world and Olympic pole vault champion Yelena Isinbayeva set a world record of 5.03 metres at Rome's Golden Gala on Friday.
The 26-year-old cleared the bar with ease to surpass the record of 5.01 she set at the 2005 Helsinki world championships.
Her nearest rival on Friday was Poland's Monica Pyrek, who vaulted 4.75.
Olympic and world champion Jeremy Wariner edged LaShawn Merritt to win the 400 metres and strike a blow against his American rival ahead of next month's Beijing Games.
Wariner had a big lead in the final straight but had to hold off a strong late surge from Merritt to win in 44.36, just a hundredth of a second ahead of the 22-year-old.
Wariner gained revenge after losing to Merritt at the US Olympic trials last week and at the Berlin Golden League meeting in June although his dominance of the event clearly remains under threat.
"I got out good, better than at the trials and in Berlin," Wariner told reporters. "I knew he'd be there at the end. I had to stay relaxed and hang in there. I've got to work hard and cut out the mistakes from here on."
Merritt was not too disappointed about the defeat.
"I did what I had to do and I feel good," he said. "I lost by one tick. You run this sort of race to get the problems out and be ready for the main ones."
Jamaican sprinter Asafa Powell's Olympic preparations suffered a setback when he pulled up with a groin strain at the end of his 100 metres heat although his manager told reporters that the problem was not serious.
Portugal's Francis Obikwelu beat Derrick Atkins of the Bahamas on a photo decision in the 100m final after both athletes finished with a time of 10.04.
South African double amputee Oscar Pistorius finished seventh in the 400 metres B race with a time of 46.62 seconds, still short of the Beijing qualifying mark of 45.55.
It was his second attempt after being cleared to compete with able-bodied athletes by the Court of Arbitration for Sport (CAS) in May.
Kenyan teenager Pamela Jelimo stayed on course for the Golden League jackpot by beating world champion Janeth Jepkosgei in the 800 metres.
Jelimo, 18, clocked 1:55.69 to beat fellow Kenyan Jepkosgei by over three seconds and claim the third of the six series wins needed for a share of the $1 million prize.
Croatia's Blanka Vlasic is the only other person still in with a chance of the big prize after she won the women's high jump with a leap of two metres.
Cuban 110 metres hurdles world record holder Dayron Robles, who last month ran 12.87 seconds to beat the previous mark set by Chinese Olympic champion Liu Xiang, blew away the field in his event with a 13.08 run.
Panama's Irving Saladino, the world long jump champion, leapt 8.3m to top the field in his comeback from a knee injury.
Finland's javelin world champion Tero Pitkamaki, who accidentally speared French long jumper Salim Sdiri in Rome last year, triumphed too with a 87.7-metre throw.
Allyson Felix, the twice 200m world champion, cruised to victory in the women's 400m race with a time of 50.25.
The next Golden League meeting is in Paris on July 18.