Yaya TourÃ© scored in both halves and Mario Balotelli continued his run of goalscoring form, converting from the spot just before the break as City condemned their Spanish opponents to a fourth straight European defeat.
But Mancini has told his side to stay focused ahead of their vital trip to Napoli in three weeks, while also maintaining their position as Premier League leaders.
“We know every game is hard,” Mancini said. “Now we have another game in 60 hours, it will be hard, we will have to change some players. We are going very well but we want to improve, this is possible.”
Ivory Coast international TourÃ© broke the deadlock after half an hour when he collected David Silva’s pass and curled a shot past Diego LÃ³pez.
And Balotelli doubled the visitors’ lead when he won a penalty and placed his effort into LÃ³pez’s bottom left corner.
TourÃ© then completed an emphatic win 20 minutes from time. Tenacious work from left-back GaÃ«l Clichy released Balotelli on a quick City counter-attack. The Italian striker found TourÃ© free on the edge of the area and the midfielder calmly slotted the ball into the net.
City captain Vincent Kompany heaped praise on his side’s defensive stability after the game.
“We put in a good shift and did everything as we planned it,” he said. “We didn’t do anything crazy, we were patient and it paid off for us.
“I think defensively this was our strongest performance in the Champions League, then our strikers are lethal on their day and they did a great job today.”
And the Belgian defender is looking forward to City’s next European tie against Napoli, when a victory will secure their passage into the last 16.
“It’s a big game, but that’s what you play Champions League for,” he added.
“We’ve always thought if we do our job properly then we are as strong as anyone. We don’t need to look too much at the other teams, we can win every game.”
Villarreal: Diego LÃ³pez, Carlos Marchena, Mateo Musacchio, Gonzalo, Mario Gaspar, CatalÃ¡, HernÃ¡n PÃ©rez (Joan Oriol, 84), Jonathan De GuzmÃ¡n (Ãngel, 76), Borja Valero, Wakaso (Gerard Bordas, 77), Joselu
Manchester City: Joe Hart, GaÃ«l Clichy, Pablo Zabaleta, Stefan Savic, Vincent Kompany, Yaya TourÃ© (Sergio AgÃ¼ero, 74), Samir Nasri, David Silva (Adam Johnson, 65), James Milner, Nigel de Jong, Mario Balotelli (Aleksandar Kolarov, 82)
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