Aston Villa manager Gerard Houllier hailed the instant impact made by record signing Darren Bent in the shock home success over Manchester City. Bent 's move from Sunderland raised eyebrows, but he quickly repaid a slice of his £18million price tag with the first-half winner against Roberto Mancini's side. It was a huge dent to City's Barclays Premier League title hopes and lifted Villa clear of the relegation zone. Houllier said: "The finish was that of a natural-born finisher, something you cannot teach somebody. That is what he is here for, to score goals. "Roberto Mancini told me before the game that I'd signed a great player and that is a tremendous start for him."