Finally, a series of heats and some direct qualifiers for the medal finals began. The wind was the exact opposite of Sunday's, so fast times were unlikely, but the racing was no less intense in St. Catherines, Ontario, Canada, at the 2024 World Rowing Championships Senior, Under 23 and Under 19.

Great Britain's Holly Youd and Anna Grace looked impressive in the first heat of the U23 women's sculls, leading for much of the race, although recent World Rowing U19 medallists from France, Lea Hersovici and Fleur Vaucoret, came through in the closing stages. Both were faster than Germany's winning time in the second heat. 

The schedule changes meant that some of the U23 men's pairs had to race two races on the same day. While eight crews qualified for the semi-finals from the heats, the rest had to race the repechage at the end of the day. The final four places were decided in the last two races and the semi-finals will take place on Wednesday. 

Tuesday's racing session was the first to feature the Senior Lightweight Women's Single Sculls, with the 22-strong field including seven Olympians at Paris 2024 a few weeks ago. So it was no surprise that Greece's Zoi Fitsiou and Romania's Ionela Cozmiuc - both medallists in the women's lightweight double sculls in Paris - won their heats. The third was dominated by Ireland's Siobhan McCrohan, the reigning world champion in this boat class. 

The penultimate boat class of the day was the U23 Women's Eight. With the USA and Great Britain having already secured their places in the medal race from Sunday's heats, the remaining five crews battled it out for the four remaining places in the A final. Despite a slow start from Romania, there was disappointment for the home nation at the finish line when Canada were the only crew not to progress. 

There will be another full day of racing on Wednesday when the first U19 rowers start their competition. Racing begins at 09:30 EST with the U19 heats starting at 10:34 local time. The full day of racing will be streamed live on the World Rowing YouTube channel. There's a non-Paralympic boat class at these championships, and today's preliminary race in the PR3 men's pair saw Italy beat Japan; they'll meet again in the final on Saturday 24 August.