THREE of the most acclaimed world records in track and field are now official after the International Amateur Athletic Federation on Monday formally ratified new records in the 100m (Maurice Greene, 9.79 seconds), mile (Hicham El Guerrouj, 3:43.13) and decathlon (Tomas Dvorak, 8,994 points). Greene smashed Donovan Bailey’s 100m mark of 9.84 seconds from the 1996 Atlanta Olympics on June 16 in Athens, Greece. El Guerrouj bettered Noureddine Morceli’s six-year-old mile mark of 3:44.39 in Rome on July 7. Dvorak broke Dan O’Brien’s seven-year-old decathlon record of 8,991 points in Prague, Czech Republic, on July 4. All three athletes are firm favorites in their events at the World Championships, which run from August 21 to 29 in Seville.