Forest Green's unbeaten start to the season came to an end at the hands of Rochdale on Saturday afternoon who came away from The New Lawn with a 1-0 win.
Kyron Gordon's first half header was enough for all three points in a tight battle in Nailsworth.
Rovers started brightly and created a golden opportunity through some good work from Kairo Mitchell, but he was denied low down by Oliver Whatmuff.
Jili Buyabu struck just wide of the far post soon after, with Ryan Inniss calling Whatmuff into further action with a header saved by the legs of the Dale 'keeper.
The visitors grew into the match and could've taken the lead on nine minutes with Emmanuel Dieseruvwe's effort saved excellently by Luke McNicholas.
Devante Rodney forced McNicholas into further action as he tipped his powerful shot over the crossbar.
Rochale took the lead just before the break through Kyron Gordon headed effort following Aidan Barlow's corner.
Half-time: Forest Green 0-1 Rochdale
Rovers almost hit back immediately after the interval with Tre Pemberton's cross volleyed towards goal by Christian Doidge but Whatmuff was there to help over the crossbar.
Rodney went close, he shifted the ball onto his right and struck an effort just wide of the upright.
McNicholas showed excellent bravery, he clawed the ball away from Dieseruvwe's path following Gordon's cross.
Rovers pressed for the equaliser but the visitors did enough for victory.
Full-time: Forest Green 0-1 Rochdale
Forest Green: McNicholas, Pemberton, Inniss, Moore-Taylor, Knowles, Mendy (Balagizi 75), Whitwell, Moore (Haughton 66), Buyabu (Kengni 75), Mitchell (Cardwell 60), Doidge (Marquez 60).
Subs not used: Pagel, Bunker.
Rochdale: Whatmuff, Gordon, East (Pettitt 84), Ebanks-Landell, Gilmour, Dieseruwve, Rodney (Smith 84), Barlow (McBride 66, Amantchi 90+10), Moss (Allarakhia 84), Berkoe, Beckwith
Subs not used: Myles, Humbles.
Attendance: 2,482 (350 away)