 Complete the following phrase:  Three track and field athletes from Botswana participated at the London games after having achieved qualifying standards in their respective events up to a maximum of 3 athletes in each event at the A Standard, and 1 at the B Standard. Track runner Isaac Makwala, competing in the mens 400 metres, did not advance into the semi-finals after finishing fourth in the heats. Amantle Montsho, Botswanas only female athlete and 2011 world champion, was favored to win Botswanas first ever medal in the 