City moved back within five points of the top as Aguero struck twice in a 4-0 home defeat of West Brom and rivals Manchester United slumped to a shock loss at Wigan.
With just five games remaining, manager Roberto Mancini claimed it was too little too late but Aguero insists no-one at the Etihad Stadium will give up of catching United.
The Argentinian, whose double took his goal tally for the season to 26, said on City TV: "Of course it was important to win, we knew we had to win as at any moment United could drop points, as happened.
"They dropped three points, which gives us more confidence to fight for the Premier League.
"We have to be focused now for all the remaining games, these five games, try to win, to win points and then (when) United come here hopefully we (will) have won every game. The most important thing is to keep winning, which can only be good."