CNN  —  Seven months ago, Manchester City’s dominance showed no signs of waning. Pep Guardiola’s men were once again lifting the Premier League trophy, basking in the glory of a sixth league title in seven years. City had secured its status as one of the league’s best-ever teams and kicked off this season in search of a fifth consecutive title. But the club is now mired in its worst-ever run of form for 18 years , a slump that continued on Saturday with a 2-1 defeat to Aston Villa. “We know how