The central midfielder made the switch to Kingsmeadow last week and was included in the squad for the weekend trip to Tonbridge Angels.
Ethan Chislett gave AFC a ninth-minute lead which they held until Jaakko was introduced at the interval. Joe Piggott made it 2-0 midway through that second-half with Troy Chiabi adding a third shortly after.
Jaakko will have further opportunities to impress in the coming weeks ahead of The Dons Sky Bet League One opener on Saturday 12 September.