Britain’s Samantha Murray gave the home crowd plenty to cheer about, finishing second in 2:08:20, which was also inside the previous Olympic record.
Murray, who is 22, is now lying third overall and will have every chance of being in contention for the gold medal if she fares well in the show jumping.
Adrienn Toth of Hungary is leading after two events, having followed up her second place in the fencing with a very respectable swim of 2:17:32.
Just behind Toth is Brazil’s Yane Marques as the athletes head to Greenwich Park for the show jumping, which is the Brzilian’s favourite event.
23-year-old Elodie Clouvel from France pushed herself up the field with a strong swim after finishing in 25th place in the fencing.
As expected, world number one Laura Asadaukaite dropped back a bit in the swim after her third place in the fencing. She completed the swim in 2:18:67 and is now in fourth place. A good ride will still leave the Lithuanian with very good medal prospects thanks to her strength in the final combined running and shooting event.
Defending Olympic champion, Lena Schoneborn of Germany, will be a little disappointed with a swim of 2:19:76. And reigning world champion Mhairi Spence was also a little short of her best form, finishing in 2:16:51.
A one-second advantage over a rival in the pool would convert into a three-second head start in the final combined running and shooting event, when the points secured in the first three events are converted into time handicaps.
As things stand, the first 26 athletes would start the combined within a minute of each over, showing just how close this event is.