As the dust settles from a pulsating first leg which saw the Manchester club snatch a last-minute winner from the gallant Championship side, former Rangers' manager McCoist has urged the Bristol City players to not get too disheartened.
"They got what they came to the Etihad Stadium for because the tie is still alive, and they should be so proud of that achievement."
The former Scottish international complimented the Premier League annihilators' attack-minded approach to the game, stating that "they did anything but park the bus".
He highlighted their ability to defend well but still show attacking intent, maintaining their discipline, organisation and determination throughout, despite the Premier League leader's equaliser in the 55th minute.
Their game plan to press high up on the pitch allowed them to steal the ball in areas where they could 'hurt City', which McCoist argues can be seen in their first goal - a penalty awarded after John Stone tried to make up for Mangala's loss of possession in Man City's third.
The 55-year-old didn't criticise the high-flying Championship team for the Manchester club's late winner either, saying that "late goals are what Man City do - and it is very hard to stop them".
City have scored late goals all season - 19 in total - and "that is not down to luck. They forced errors and created spaces. Chances followed and, eventually, so did a goal," the Scot explained.
However, like most neutrals, McCoist knows the second leg at Ashton Gate will be an interesting match-up, especially since three of their four wins against Premier League clubs in the Carabao Cup this season have come from home, including their glorious win over holders Manchester United in the quarter-finals. So there are plenty of reasons why the 'Robins' will believe they can overturn the deficit and reach the final at Wembley.