Rickie Lambert's 35th-minute free-kick proved enough to seal a 2-1 win at St Mary's after an early opener from Jay Rodriguez had been cancelled out by a header from John Terry.
Chelsea's shock loss allowed Tottenham to leapfrog into third place with a 2-1 win at Swansea.
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Amanda Houston has Wednesday's forecast for the west of the region.
Amanda has Wednesday's forecast for the east of the ITV Meridian region.
Amanda Houston has the lunchtime forecast for the west of the ITV Meridian Meridian region.