Dagenham & Redbridge claimed their first win of the National League season thanks to a first-half goal from Paul McCallum.
Having drawn with Gateshead and Eastleigh, either side of defeat at Woking, Daggers gave Sam Ling his first start of the season, while Ryley Scott was included on the bench.
And the hosts had their first chance on six minutes when David Longe-King's clearance found McCallum, but his header lacked power to trouble visiting keeper Daniel Gyollai.
Captain Matt Robinson then drilled a cross into the box on 12 minutes but a Maidenhead defender managed to avoid steering the ball into his own net and clear the danger.
And Gyollai saved a 25-yard shot from Josh Hare, after good work from Junior Morias, on 19 minutes, before Daggers took the lead before the half-hour mark as McCallum claimed his third goal of the season.
Great work between Ling and Mo Sagaf on the right, led to a cross from the latter which McCallum slotted home.
And, after Robinson was booked, Elliot Justham saved the resulting free-kick from Dan Sparkes to keep the home side in front.
Ling made way for Myles Weston during the break, with the new arrival drawing a foul from Sam Beckwith, who earned a booking, on 50 minutes.
And Daggers went close to doubling their advantage five minutes later when Weston's cross found McCallum but his shot was deflected behind.
Weston led a quick counter just past the hour and crossed for Mauro Vilhete, whose mishit shot fell for McCallum, but he fired over the bar.
And after the Magpies made a triple substitution, more great work from Weston saw him cut inside and see a shot deflected behind for a Daggers corner on 71 minutes.
Justham made a great save to keep out a powerful header from a Maidenhead corner moments later and, after denying Adrian Clifton on a one-on-one, saw Nik Tavares keep the rebound out to protect the home side's lead on 76 minutes.
McCallum then found himself through on goal at the other end, only to be denied by Gyollai, and Daggers had a let-off six minutes from time when a Maidenhead effort was cleared off the line.
Vilhete was replaced by Manny Onariase in the closing stages as Daggers looked to hold onto their slender lead in the face of mounting Maidenhead pressure.
And Scott came on for his first appearance of the season in place of Elliot Johnson as the match entered four minutes of stoppage time.
Man of the match Justham then produced a stunning save to keep out Cole Kpekawa's header and ensure all three points for McMahon's men.
Dagenham & Redbridge: Justham, Hare, Longe-King, Johnson (Scott 90), Ling (Weston 46), Vilhete (Onariase 87), Tavares, Robinson, Sagaf, McCallum, Morias. Unused subs: Strizovic, Walker.
Attendance: 1,270 (including 53 Maidenhead fans).
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here