Scotland’s Katie Shanahan marked her Olympic debut by booking her place in Monday evening’s 400m individual medley final.

The 20-year-old finished fourth in her heat, with her time of four minutes 40.40 seconds good enough to secure her passage.

There was however disappointment for another Scot, Kathleen Dawson, in the 100m backstroke as she failed to make the semi-finals.

Shanahan said: “I am really excited. I am really happy going into the final and hopefully I can put down my best performance and think if can get a personal best (PB) I would be happy.

“I know the field in there is really strong so I’m just going to see what I can do.”

Shanahan was cautious about her chances of getting onto the podium, and is instead focusing on producing her fastest-ever time rather than thinking about a medal.

She added: “Never say never, I think Summer [McIntosh] is definitely going to be winning it, and I think the top two is definitely open for anybody in that field.

“I am not really going in looking for a medal, that is not something I would ever go in saying but if I can get a PB and see how close I can get to being in the medals I will be happy.”

Dawson, 26, finished fifth in her heat but her time of one minute 00.69 seconds was not good enough to take her to the semi-finals.

She said: “It is disappointing to have come away with the time I swam – I don’t think that was an accurate representation of where I feel I am right now.

“I walked out and I was so happy to be there and I still am happy to have gone out and experienced what just happened because I didn’t have a crowd in Tokyo.

“I really enjoyed that it is just a shame to come away with the time that I did.”