Vincent Kompany admits Manchester City's sloppy pre-season was a wake-up call for the squad.
They blew West Brom away on Monday to open their Barclays Premier League campaign in style.
Kompany sealed a 3-0 win with a second-half header after Yaya Toure and David Silva - after his flick deflected in off Craig Dawson from Toure's initial shot - put City in control.
They lost 4-2 at Stuttgart 10 days ago and captain Kompany believes the defeat gave them inspiration to improve.
"We came out with a point to prove," the defender told the club's official site.
"Last week, when we played against Stuttgart, it was a really poor performance and that was actually a good thing for us because we knew we had to work on a lot of things.
"If you look at the training sessions we did last week, you'll see this is a team with a lot of intensity. Seeing the faces, I knew the team would be ready for this game."
It was a stroll for Manuel Pellegrini's men with West Brom offering little resistance as new £12million record signing Salomon Rondon watched from the stands.
And boss Tony Pulis, who admitted he got his tactics wrong against City, still wants to do more business.
He told the club's official site: "We need to strengthen the axis of the team. We will try to do that during the coming period. But as I've said before they have to be the right player.
"Any player we bring in has to strengthen the squad."