Boro arrived in Dorset`s county town having scored 10 goals in their previous two matches, but found the Magpies too hot to hand.
Steve Thompson`s side, playing a fourth consecutive home game, were unable to break the deadlock in the first half, and it was Boro`s vastly experienced striker Jamie Cureton who came closest to scoring.
But the second half saw the Magpies take the lead 8 minutes in when Ed Bastick profited from good work from Antonio Diaz to put the hosts in front.
And then 7 minutes from time, Dorchester doubled their lead with Bastick again being on target to beat visiting `keeper Aiden Upward after being set-up by Billy Lowes.
It was sub Sam Lanahan who got his name on the scoresheet in the 84th minute to make it 3-0 from close range, and then a minute into stoppage time, Mo Baghdadi, who scored four times at the weekend, added a fourth after good work from Lanahan.
The win didn`t move Dorchester any higher than twentieth in the table, but pulled them to within two points of Farnborough in sixteenth.
By Steve Whitney
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