Rudisha was only a semi-finallist at last year's World Championships
David Rudisha has broken the 800m world record for the second time in eight days at a meeting in Rieti, Italy.
The 21-year-old Kenyan ran one minute 41.01 seconds to better the time he recorded in Berlin last Sunday by eight hundredths of a second.
The previous best of 1:41.11, set by Denmark's Kenyan-born Wilson Kipketer's had stood since 1997.
At the same meeting, Jamaican Nesta Carter equalled Tyson Gay's fastest time of 2010 over 100m - 9.78sec.
Assisted by a tail wind of +0.9, Carter won ahead of second-placed American Ryan Bailey, who ran 9.88, with another Jamaican Mario Forsythe third in 9.95.
Kipketer happy to cede record to Rudisha
Rudisha was confident he could break the record and believes he can lower the world record.
He said: "I just knew I was in good shape. The conditions were perfect. I expected to break two records in seven days.
"I cannot say now what I need to improve. I will see in training with my coach what I can improve but I think I need to change only small details."
Rudisha is the African champion over the distance but only reached the semi-finals of the 2009 World Championships.
However, he ran Kipketer's mark close at a meet in the Belgian city of Heusden-Zolder in July with a time of 1:41.51 - the closest anyone had got to Kipketer's record.
And Rudisha returned to the scene of his disappointing showing in the World Championships, the German capital's Olympic Stadium, to beat Kipketer's 1997 time.
And his prediction in the immediate aftermath of that feat that he would go even faster proved correct as he again set a fresh marker in central Italy on Sunday.
Rudisha was taken through the bell by compatriot pace-setter Sammy Tangui in 48.20sec before taking off on his own to win by almost two seconds from Boaz Kiplagat Lalang, also from Kenya.
American Nick Symmonds was third in 1:43.76, while Briton Michael Rimmer took fourth in a personal best 1:43.89.