A first half goal from Glen Harris was enough for Slough to earn their first win at Stompond Lane since an FA Cup win in 1979 and their ninth in twenty six attempts.
Slough had the better of the exchanges in the first half but it wasn't until the thirty sixth minute that the breakthrough came. Mark West, having earlier gone close with a bicycle kick from close range, showed a cool head and threaded the ball through to Harris who replicated the assistant managers calm assurance and picked his spot to finish past Ricky Perks.
The home side, occupying a play off position at the start of play, were pressing for an equaliser in the second half, but Slough were defending resiliently and Masters was rarely troubled when the Swans did get a sight of goal. Sub Jamie Reeve and Sam Keevil both had such opportunities, but both efforts were tame and Masters was able to smother both shots easily.
Masters did have to extend himself when a shot from Simon Huckle saw the keeper get his fingertips to the Walton players weak shot across goal, but it still needed a save to turn the ball away for a corner.
Slough nearly got a second was a ball across the face of the area from George Moleski was turned inches wide of the far post by Walton sub Bob George.
Walton had a lifeline though as Tristan Frontin made a run into the area to collect a headed through ball from Bobby Traynor and as Steve Daly came across and took the ball, the referee saw it differently and awarded a penalty. Neil Lampton struck the penalty well but it was fairly central and despite Masters diving to his right, he was able to deflect the ball away with his legs and Traynor fired the ball over from the edge of the box.
Slough did get the ball into the net again through Ian Hodges after a great run down the left wing from Leon Woodruffe which saw the full back round three Walton players before his cross shot was converted from close range at the far post, but the linesmans flag went up and the striker was ruled offside.
Walton & Hersham Line up
Ricky Perks, Will Jenkins, Wes Goggin, Danny Lavender, Sean Thurgood, Tristan Frontin, Neil Lampton (c), Sam Keevil, Ben Thorne, Simon Huckle, Bobby Traynor. Subs: Bob George (for Frontin), David Francis, Jamie Reeve, Scott Edgar (for Thorne), Gary Haylock.