Promotion-hopefuls Oldham crashed to defeat as Bournemouth produced only their second away win of the season.
Bournemouth went ahead when David McGoldrick turned on the edge of the box and beat keeper Alan Blayney.
The Cherries quickly doubled their lead when Bjarni Vidarsson fired in from 12 yards after being set up by McGoldrick.
Oldham pulled a goal back on half-time when Chris Porter was dragged down in the box by Neil Young, and Andy Liddell struck home the spot-kick.
Oldham: Blayney, Lomax, Turner, Gregan, Charlton (Smalley 87), Liddell, Wellens, McDonald (Rocastle 78), Taylor (Edwards 26), Porter, Warne.
Subs Not Used: Ryan Smith, Pearson.
Sent Off: Turner (90).
Goals: Liddell 45 pen.
Bournemouth: Moss, Young (Hollands 66), Broadhurst, Gowling, Wilson, Cooper, Browning, Vidarsson (Pitman 46), Cummings, McGoldrick, Fletcher (Purches 46).
Subs Not Used: Stewart, Hart.
Booked: Broadhurst, Moss, Young, Browning, Hollands, Wilson.
Goals: McGoldrick 29, Vidarsson 31.
Ref: G Laws (Tyne & Wear).