The unexpected loss brought an end to Notts County's amazing 25-match unbeaten run. They had not lost a game in the league since 17 September.
The Daggers, led by Steve Gritt and Dave Jupp, managed to halt Notts County's second seven-match winning streak of the season.
Notts County took the lead in the 21st minute through Ruben Rodrigues' 14th goal of the season. However,
Angelo Balanta equalised for Dagenham ten minutes later. Although Jodi Jones and Macaulay Langstaff hit the post for Notts County, they were unable to convert their chances.
In the 86th minute, second-half substitute Inih Effiong scored the winner for the visitors, despite five minutes of added time and a frenzied goal-line scramble.
The 7,441-strong home crowd was left disheartened, as Notts County's lead at the top of the table was reduced to just two points over second-placed Wrexham. Wrexham, who have two games in hand, could overtake Notts County and go top if they win their next match against Chesterfield on Tuesday night.
The Daggers' victory was their second consecutive win, which lifted them to 10th place in the table, within three points of the play-off contenders.
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