Manchester City manager Roberto Mancini was unhappy with his side's defending for the second game in a row.
City qualified for the fourth round of the FA Cup with a 4-2 win over Leicester City just days after conceding three goals against Wolves in their 4-3 league triumph.
Mancini admitted that his side came good after a slow start against the Foxes but was not pleased with the overall performance, especially from his defenders.
"It is always difficult in the FA Cup," he said. "Leicester played very well in the first 20 minutes but after we played better and scored the three goals.
"But again in the last 15 minutes, like against Wolves, we thought that it was finished and we conceded another one.
"We must improve. We have conceded a lot of goals in the last three games, so we must be sure to work hard."
