There is a gruelling day ahead for Team Ireland's Aileen Morrison as she competes in the women's triathlon, which includes a 1,500m swim, a 43km bike ride and 10km run.
We then turn to two naturalised Irish citizens as Latvian-born Sanita Puspure pushes for a win in the C Final of the women's single sculls this morning, while Tori Pena - originally from California - aims to qualify for the final of the pole vault.
Aileen has started in the triathlon.
It is said a top 12 finish would be good for her.
Cycling will take up our attention later this morning with Martyn Irvine in his flying lap while at the same time Cian O'Connor and Billy Twomey lead the Irish charge for medals in the individual jumping at the Equestrian.
It is pretty hard at the moment to determine where Aileen is, all the swimmers are bunched up together apart from a five leaders ahead of them.
Sandwiched in between the equestrian and the sailing, which starts at 12 noon, is Stephanie Reilly's bid to qualify for the final of the women's 3,000m steeplechase. Around lunchtime, while the sailing is still ongoing, we go to the ExCel Arena to see how Paddy Barnes does in the men's light fly boxing before we finish the afternoon with more sailing. Martyn Irvine then returns for his second event, the 30km points race, in the men's omnium track cycling.
No dirty tactics so far, surprising considering the swimmers are bunched up together.
Aileen had finished second twice in two major competitions this year and third in Hamburg last year, so she is definitely a competitor for a medal.
British competitor is first out of the water to a big cheer.
Aileen has come out of the water in 35th about a minute and 19 seconds behind the leader.
The Brazilian Oliveira has fallen off her bike onto hard tarmac. That will hurt and must put her out of medal contention.
And she was in fourth too, so it is a disaster for the Brazilian.
Quick comment from Fionnuala Britton from late last night - she was happy the Japanese trio took it on early so she could tuck behind and let them do the work, unlike at the Europeans where she had to do it all on her own. Her thought on the track was that her tactics were working well, until the big East African kick... and that was that. She wanted better, and is now aiming for the rest of the week.
Aileen has dropped to 42nd, 1 minute 33 seconds behind the leader at the first transition.
A Polish athlete has now crashed in the triathlon at the same place as the Brazilian went down.
Two more girls have fallen in the triathlon. They just missed Aileen on that slippery corner.
After the end of the second lap, Aileen is still in 42nd place, 2 minutes and 33 seconds behind the leader.
She would have expected to be a bit closer to the leaders by now, but there are still five bike laps to go and the running too.
And that notorious corner has claimed another victim.
Great to see a lot of tri-colours at the triathlon course.
The slippery conditions have claimed a few more riders.
Aileen is now in 43rd place, 2 minutes and 59 seconds behind Team GB's Lucy Hall who leads after three laps.
It has to be said that the cycling is Aileen's worst discipline of the three, by her own admission.
The day is getting a bit warmer now in London so that might help dry out the cycling route.
Don't forget that Cycling will take up our attention at about 10.30am with Martyn Irvine in his flying lap while Cian O'Connor and Billy Twomey lead the Irish charge for medals in the individual jumping at the Equestrian.
After lap four, Aileen is 42nd, 3 minutes and 58 seconds behind leader Svenja Blazen from Germany.