Chesterfield withstood a great second-half rally by Darren Ferguson’s Peterborough to leapfrog them in the League One table.
Spireites, buoyed by the 3-2 win at Gillingham, recorded back-to-back league wins for the first time since the opening two games of the season.
But it looked as though they might slip, as from a comfortable 3-0 up after 53 minutes, they were pegged back to 3-2 with a nail-biting 20 minutes to go as Posh fought back in a fiery second half that saw six bookings,
The four Chesterfield men to be cautioned were Sam Clucas, Oliver Banks, Ritchie Humphreys and Charlie Regan while Posh’s Mendez-Laing and Christian Burgess went into the bok.
Chesterfield went in front with a ninth-minute own goal by Joe Newell and Admand Gnanduillet made it 2-0 with a 33rd-minute left-shot.
When leading scorer Eoin Doyle added a third from outside the box after 53rd minute the Spireites looked home and dry.
But Michael Bostwick headed Ferguson’s men back into it in the 61st minute and nine minutes later Marcus Maddison reduced the deficit to 3-2 with a long-range effort.
Chesterfield: Lee, Darikwa, Evatt, Raglan, Clucas, Boco, Hird, Humphreys, Roberts, Gnanduillet, Doyle
Subs: Wright, Gardner, O’Shea, Jones, Ariyibi, Banks, Beresford.
Peterborough: Alnwick, Newell, Smith, Burgess, Zakuani, Payne, Bostwick, Beautyman, James, Oztumer, McLean. Subs: Day, Vassell, Santos, Anderson, Washington, Mendez-Laing, Maddison.
Ref: David Coote (Notts).