Gloucestershire 191 (van Buuren 56, Procter 5-42) and 267 for 4 (Hammond 94, Lace 67*, van Buuren 53*) beat Northamptonshire 327 (Rossington 94) and 129 (Higgins 5-46) by six wickets
Miles Hammond, Tom Lace and Graeme van Buuren led Gloucestershire home in a chase of 266 to complete a remarkable turnaround as they beat Northamptonshire by six wickets at Bristol.
Having polished Northants off for just 129 in their second innings, the hosts were left with two-and-a-half sessions to complete their comeback.
Hammond gave them an excellent platform with 94 before Lace's unbeaten 67 and van Buuren's 53 not out - his second half-century of the match - saw the Glosters home.
It was an extraordinary result with Gloucestershire having been 153 for 9 replying to 327 on day two. But they dominated the final two days of the game and, after bad light had significantly curtailed play on the previous three evenings, Nevil Road was bathed in sunshine for the denouement.
Northants resumed 92 for 7, leading by 228. Tom Taylor was quickly trapped lbw by Ryan Higgins and when Ben Sanderson edged Tom Price behind for only 1, the end appeared swift.
But Simon Kerrigan made 27, clearing his front leg to smear three boundaries over mid-on and pulling Price off a top edge for six. It was a sedate ending - pushing at Higgins and being bowled by one that seamed back as Higgins finished with 5 for 46.
That boost to the target felt like it would give Northants enough to bowl at considering what had gone before in the game and the visitors plucked out two of the top three cheaply.
Hammond flashed an edge through the high hands of Emilio Gay at third slip when only six and he went on to punch Luke Procter off the back foot and whip him over midwicket for four.
Another boundary off Procter, slapping a short wide delivery through mid-off, raised a half-century in 137 balls and he and Chris Dent looked to be taking their side to tea in great shape. But Dent fell for 26, caught behind defending at Kerrigan's left-arm spin, and 143 were left in 32 overs after tea.
Hammond couldn't reach his hundred, bowled by Taylor to one that nipped in from round the wicket but Lace and van Buuren took up the chase.
Van Buuren slog swept Kerrigan for six and pulled a full toss for another maximum in his 43-ball fifty and it was left to Lace to sweep the winning boundary off Rob Keogh.
Graeme van Buuren
Northants vs Gloucs