Worcestershire were beaten by one wicket after being in control for lengthy periods of their 50 over friendly match with Gloucestershire at New Road.
Gloucestershire had been reduced to 117-8 in pursuit of Worcestershire's 268 all out of which Joe Leach had made a half century and then also contributed four wickets, three of them in his first spell.
But Robbie Montgomery featured in stands of 88 with Cameron Herring and 67 with David Payne to earn an unlikely victory for the visitors by the narrowest of margins.
Montgomery finished unbeaten on 96 after hitting Ross Whiteley for six over the short Cathedral side boundary to conclude the match in the 47th over.
With Daryl Mitchell having not returned from MCC duty against Yorkshire in Abu Dhabi, Tom Kohler-Cadmore opened the batting alongside Richard Oliver after Worcestershire were put into bat.
Oliver, who scored 103 and 63 in his two knocks in Abu Dhabi, looked in fine form and picked up three boundaries in the opening over from James Fuller which cost 15 runs.
Kohler-Cadmore (1) was bowled in the second over of the innings – from Payne – after coming down the wicket.
New batsman Tom Fell (24) produced some pleasing drives before falling to a fine catch by Chris Dent on the deep cover boundary off Payne.
Former Gloucestershire batsman Alex Gidman, who was skippering the side in Mitchell's absence, was trapped lbw by Matt Taylor for 2.
Oliver's knock ended on 37 when he aimed a shot over mid wicket and was bowled by Benny Howell. It became 79-5 in the 16th over when Alexei Kervezee (8) was also a victim of Howell.
Ross Whiteley was adjudged lbw to Robbie Montgomery for 10 and Ben Cox (39) holed out to mid off against Miles Hammond at 146-7 in the 30th over after some clean hitting.
Leach came in at number nine and added 49 in eight overs with Brett D'Oliveira who made 37 before being dismissed by Howell.
Leach was given excellent support in a ninth wicket stand of 73 with Jack Shantry who was the county hero in his last appearance at New Road in the promotion-clinching win over Surrey in September.
Leach's fine innings came to an end on 59 at 268-9 when he miscued Taylor to point and Shantry (28) fell at the same total when he was caught by Payne at long off.
Shantry took the new ball and struck in his first over when Will Tavare (0) drilled a delivery straight to Leach at mid-off.
The left armer broke through again when he held onto a fine return catch to account for Hamish Marshall (5).
It became 33-3 in the 10th over when Leach, who replaced Charlie Morris at the Diglis End, removed Ian Cockbain (16) who fell to a superb catch by Kohler Cadmore at second slip away to his right.
Former England keeper Geraint Jones made a breezy 26 before being bowled by Leach who claimed a third victim when Chris Dent (19) edged through to Gidman at second slip to leave Gloucestershire on 81-5.
Whiteley came into the attack and had Benny Howell caught behind by Ben Cox who then stumped James Fuller (17) off spinner D'Oliveira.
Miles Hammond (10) went for one ambitious shot too many after hitting Whiteley for two boundaries and he was bowled by the former Derbyshire all-rounder.
Montgomery and Herring added 88 in 12 overs for the ninth wicket.
Leach returned to the attack and accounted for Herring (42) who was superbly caught by D'Oliveira over his shoulder running back to long on with the total 205-9.
Montgomery reached his half century out of 218-9 in the 41st over with a six backward of square in Leach's final over and again cleared the ropes over long on off the last ball of the same over.
He was still there at the close to help Gloucestershire over the winning line with Payne unbeaten on 10.
Oliver b Howell 37
Kohler-Cadmore b Payne 1
Fell c Dent b Payne 24
Gidman lbw Taylor 2
Kervezee c unknown b Howell 8
Whiteley lbw Montgomery 10
Cox c Payne b Hammond 39
D'Oliveira c Taylor b Howell 37
Leach c Hammond b Taylor 59
Shantry c Payne b Taylor 28
Morris not out 0
Total (all out) 268 in 47 overs
FOW: 17, 58, 64, 74, 74, 79, 107, 146, 195, 268, 268.
Bowling: Fuller 9-1-62-0, Payne 8-0-35-2, Taylor 10-0-37-3, Howell 6-0-50-3, Montgomery 6-0-31-1, Hammond 8-0-49-1.
Tavare c Leach b Shantry 0
Dent c Gidman b Leach 19
Marshall c and b Shantry 5
Cockbain c Kohler-Cadmore b Leach 16
Jones b Leach 26
Howell c Cox b Whiteley 12
Herring c D'Oliveira b Leach 42
Fuller st Cox b D'Oliveira 17
Hammond b Whiteley10
Montgomery not out 96
Payne not out 10
Total (for 9 wickets) 272 in 46.2 overs.
FOW: 0, 10, 32, 66, 81, 81, 106, 117, 117, 205.
Bowling: Shantry 8-2-32-2, Morris 10-0-42-0, Leach 10-066-4, D'Oliveira 10-0-69-1, Whiteley 8.2-0-52-2.
Umpires: W Smith and R Julian.