Teddington dismissed Southgate for 80 on their way to a comprehensive seven-wicket victory that kept them on top of the 2012 Middlesex ECB Premier League.
Eastcote beat Hornsey by six wickets and Winchmore Hill beat Brondesbury by 27 runs to keep it tight at the top; Teddington lead the pair by just four points.
Twickenham consolidated their position on top of Division Two by beating Ickenham by four wickets. They now have 41 and are being put under pressure by Richmond, who are seven points behind after beating Acton by seven wickets.
Harrow St Mary's dismissed Enfield for 85 en route to a nine-wicket win that helped their cause and they lead Division Three by six points.
The full results and tables are attached.
© Cricket World 2012
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