Team GB's 200m freestyle finalist Caitlin McClatchey considered retirement after Delhi Commonwealth Games

Caitlin McClatchey will be competing in tonight's 200m freestyle (Getty Images)

Caitlin McClatchey will be taking part in tonight's 200m freestyle but there was a time when she was considering retirement from swimming.

The Scot toyed with quitting the sport altogether following the Commonwealth Games in Delhi, India, in 2010. There, she failed to make an individual final, finishing fifth in three relays.

But she opted to stay within British Swimming and changed coaches to Ian Armiger, a decision that appeared not to have paid off when she missed out on qualifying for the British team at the initial Olympic trials at the Aquatics Centre in London.

However, McClatchey booked her spot in some style at the subsequent trials in Sheffield in June and, in what is her third Olympics, appears to be thriving on the expectation and roars of the home crowd.

McClatchey, whose parents both swam for Scotland in the Commonwealth Games and whose uncle, Alan, won Olympic bronze in 1976, said: “I’ve really worked hard in the last couple of years. I’ve considered quitting swimming . . . But I stuck at it and I’m so pleased I’ve got into an Olympic final.”

The 26-year-old, who will quit the sport after London and has talked of a possible career in Scottish politics in the future, has been in this position before. She lined up in the final of the 200m freestyle in Beijing and came away sixth. Last night, she was tellingly the sixth-fastest qualifier. She will do well to employ her semi-final tactic of going out hard and trying to stay there. She added: “All bets are off and times don’t matter at all.”

As she had done in her heats, McClatchey credited the crowd for getting her into the final, a race in which she said they would once again play a vital role.

“The crowd are fantastic and I know they will be from the moment I step out there for the final,” she said. “They really lifted me before.”

McClatchey knows her strong qualifying display will provide no guarantee of a medal. Her boyfriend, Liam Tancock, was third fastest going into the 100m backstroke final but finished fifth in last night’s final.

Tancock, whose result was a one-place improvement on Beijing, refused to be despondent and preferred to focus on the progress he has made in the event. “I’m pretty pleased,” said the Evening Standard columnist. “I’ve progressed in the right direction.

“It didn’t come off with any medals. I still got to the top five and it’s a pretty special achievement.”

Tancock has already set his sights on claiming an Olympic medal at the next Games, in Rio de Janeiro.

He added: “I wake up every morning with the same dream. That’s what gets me up in the morning and why I train hard. I look to the future and Rio. Only one guy can achieve the dream and that was Matt Grevers.” Tancock has another event in the form of the 4x100m medley relay in which he will again swim the 100m backstroke. He said: “We’re not expected to do too much but who knows, we can just go out and swim fast.”

Hannah Miley is Britain’s other finalist in the pool tonight. McClatchey’s fellow Scot, who had been tipped to pick up a medal in the 400m individual medley on ­Saturday but faded in the final, looked lacklustre in finishing 10th in the heats of the 200m individual medley. But she returned to the Aquatic Centre for last night’s semi-finals to clock the seventh quickest time, although a medal looks an unlikely outcome.

The gold looks likely to be placed over the formidable shoulders of Ye Shiwen.

There have been doping suspicions about the 16-year-old Chinese swimmer’s fine form in the Olympic pool and she was left to defend her actions and those of her Chinese team-mates once more.

She said: “I just train well and perform well and keep on going.”

The eight finalists:

Kylie Palmer AUS 1:57.44

Veronika Popova RUS 1:56.84 Camille Muffat FRA 1:56.18

Bronte Barratt AUS 1:56.08

Allison Schmitt USA 1:56.15

Federica Pellegrini ITA 1:56.67

Caitlin McClatchey GBR 1:57.33

Missy Franklin USA 1:57.57

Watch Caitlin in tonight’s 200m freestyle final at 7.41pm (BBC1