Watford became the first Premier League team to sack three managers in a season when Nigel Pearson departed on Sunday, but the change of management made little difference as City bounced back from their weekend disappointment of losing an FA Cup semifinal to Arsenal.
City had thrashed Watford 8-0 earlier in the season and 6-0 in last season’s FA Cup final and there appeared little belief from the hosts of causing an upset from the off.
Hayden Mullins took charge on a temporary basis for the second time this season and set up to frustrate the visitors by defending deep with little threat of ever testing City’s soft spot at the heart of their defence.
Ben Foster delayed the floodgates opening with a stunning save after Rodrigo’s shot deflected off Gabriel Jesus.
However, there was little doubt over the outcome once Sterling controlled Kyle Walker’s cross and fired powerfully into the top corner on 31 minutes.