And minutes later, Joel Byrom set up Lawrie Wilson, whose fierce strike from just inside the penalty area extended Boro's lead.
A powerful second-half free-kick from Ricky Wellard was the Dons' only decent chance and their fate was sealed by a late drill home from Eddie Odhiambo.
AFC Wimbledon: Brown, Conroy, Lorraine, Johnson, Blanchett, Hatton, Gregory, Hendry (Elder 46), Wellard, Kedwell, Moore (Poole 65). Subs Not Used: Pullen, Judge, Adjei.
Stevenage: Day, Henry, Roberts, Ashton, Laird, Wilson (Odhiambo 74), Bostwick, Drury (Albrighton 90), Byrom, Beardsley, Sills (Griffin 67). Subs Not Used: Bayes, Vincenti.
Booked: Beardsley, Drury, Bostwick.
Goals: Roberts 9, Wilson 11, Odhiambo 90.
Att: 3,840
Ref: Rob Lewis (Shropshire).
Source: BBC Sport
Source: BBC Sport