WEYMOUTH must bridge a nine-point gap to Vanarama National League safety after Maidenhead United shocked Boreham Wood 2-0.
David Oldfield's Terras had closed to within six points of 20th-placed Maidenhead after beating Eastleigh 1-0 in midweek.
However, Alan Devonshire's men scored a goal either side of half-time in front of the BT cameras after Wood's Kane Smith had wobbled the bar with a first-half header.
United then wrapped up the three points courtesy of Josh Kelly and Nathan Blissett to end the Wood's 12-game unbeaten league run.
Wood had not lost since a 2-1 defeat at Chesterfield in late October and have reached the fifth round of the FA Cup where they are due to visit Premier League side Everton.
READ MORE: Weymouth's trip to Altrincham postponed amid Storm Eunice
After the postponement of their trip to Altrincham, on whom they hold a game in hand, Weymouth still have 16 league games remaining to achieve safety.
The Terras are next in action at home to Bromley on Tuesday (7.45pm).
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