Posh bowed out of the Emirates FA Cup after a 1-0 defeat to Barnsley at the Weston Homes Stadium.
Peterborough United were knocked out of the Emirates FA Cup at the second round stage as fellow Sky Bet League One side Barnsley earned a 1-0 victory at the Weston Homes Stadium.
A goal in the final quarter of the game from Patrick Kelly secured a passage into the third round for the Tykes, who produced the best chances in the contest devoid of a lot of quality.
Davis Keillor-Dunn headed over on seven minutes before Declan Frith found the side-netting after a forceful run into the box at the other end.
Goalkeeper Murphy Cooper got away with an apparent handball out of the box moments later after Frith was slipped through by Matt Garbett and two minutes before the break, Frith saw a curling effort headed off the line by a Tykes defender.
However, that momentum at the end of the first half was not replicated in the second half with Russell, and Kelly both going close, the latter heading straight at Bass.
Ben Woods fired a free-kick over the crossbar and Mills was denied by Cooper before further efforts at the other end were thwarted by Bass.
However, the Posh goalkeeper couldn't do anything about the goal that ultimately won the contest as the visitors went back to front, with a low centre converted from close-range by KELLY.
Bass made two further saves before the end, but apart from a flurry of bookings, there was nothing else to write home about as Posh suffered a fourth successive defeat in all competitions.
Posh: Bass, Collins, Frith (sub Leonard 65min), Lees, Woods (sub Khela 61min), Lisbie, Lindgren (sub Morgan 65min), Mills, Okagbue, Garbett (sub Odoh 65min), Dornelly. Subs: Reyes, Johnston, Lolos, O’Brien-Brady, Kioso.
Barnsley: Cooper, Russell, De Givigney, Vickers, Phillips (sub Connell 46min), Jalo (sub Kelly 46min), Gent, Rooney (sub Watson 58min), Farrugia, Bland, Keillor-Dunn (Sub Farrell 64min). Unused subs: Smith, Cleary, Barratt, Graham, Yoganathan.
Half-time: Peterborough United 0-0 Barnsley
Full-time: Peterborough United 0-1 Barnsley
Attendance: 4,157 (561 Barnsley fans)
Referee: Alan Young