Caylan Vickers' deflected strike gave Barnsley a 1-0 victory at Peterborough that maintained their encouraging start to the League One season.
The Tykes have picked up 10 points from their first four fixtures, in contrast to the Posh, who remain without a point and without a league goal from open play in their campaign.
A Cagey Opening Springs to Life
It took 38 minutes for the game's first chance of note, as Kyrell Lisbie pulled the ball back for Klaidi Lolos, whose shot was beaten away by Murphy Cooper.