Boreham Wood saw their Vanarama National League promotion push dented after losing 2-0 at Maidenhead.
The visitors, who face Everton in the FA Cup fifth round next month, had gone close to breaking the deadlock when Kane Smith saw his curling shot rattle the crossbar.
However, it was the Magpies, looking to pull further clear of the relegation zone, who took the lead when Josh Kelly cut back inside onto his right foot before drilling a low shot into the far corner.
Third-placed Boreham Wood, who had not suffered a league defeat since October, pushed for an equaliser and Connor Stevens headed just wide from a corner.
Maidenhead, though, added a late second through a 20-yard volley from Nathan Blissett to move nine points clear of the bottom three.
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