MANCHESTER, England, Nov 15 (Reuters) - Manchester City made the most of a late first-half collapse by Manchester United ( MANU ) to score twice just before the break as they secured a 3-0 derby win on Saturday that put them four points clear of second-placed Chelsea in the Women's Super League.

Defender Rebecca Knaak headed City into the lead in the 26th minute but it was United's collapse just before halftime and an inability to get shots on target that put paid to any ambitions they might have had of winning the hotly-contested derby.

Khadija Shaw netted for City in the 43rd minute with a typical poacher's effort from Kerstin Casparij's low cross, and things went from bad to worse for the visitors in stoppage time as an attempt to play out from the back went badly wrong, allowing Lauren Hemp to thump home a third.

United's best effort came from a former City player when summer signing Jess Park hit the outside of a post, but that was as close as they came as their hosts moved to 24 points after nine games, four ahead of Chelsea, who play Liverpool on Sunday, and seven ahead of third-placed United.