Glamorgan 203 (Root 51*) and 264 for 9 (Selby 73, Hannon-Dalby 4-59) drew with Warwickshire 186 (Bell 50) and 347 for 7 dec (Bell 90, Mousley 71, Hain 65)
Glamorgan battled bravely to a draw in their final Bob Willis Trophy match of the campaign, as Warwickshire's Ian Bell brought down the curtain on his 20-year first-class career at Sophia Gardens.
Their valiance in the closing overs notwithstanding, the result ends a disappointing four-day campaign for Glamorgan, whose batsmen have failed to get going throughout the competition, despite a rotation policy which has seen a number of fringe players being handed opportunities in the top order.
Bell's final contributions yielded 140 runs for the county he's served so well, and he was given an ovation by both teams, umpires and coaching staff as he left the field for the final time.
Resuming their pursuit of 331 on 9 for 0 on the final morning, Glamorgan were 69 for 2 at lunch and much credit goes to Nick Selman in the afternoon for his defiant innings of 73 as he battled hard to save the match.
The final's day play would also prove to be a big test of character for Glamorgan's Joe Cooke, in only his second first-class county red-ball match, as it quickly became evident that Glamorgan would employ a rear-guard action.
Alongside Selman, the 23 year-old left-hander took control to successfully see off Oliver Hannon-Dalby and Liam Norwell in the opening exchanges, with the best shot of the morning coming from an off-drive to the boundary.
However, having batted defensively and patiently in the first hour, Glamorgan lost two wickets from successive Ryan Sidebottom deliveries, when Cooke edged tentatively to the keeper before Owen Morgan was bowled by an in-swinging full-toss.
The Welsh county's defensive approach, having effectively given up the pursuit of 331, backfired after lunch as captain Chris Cooke, attempting a back-foot drive through the off-side, feathered to the keeper off Hannon-Dalby.
It looked like being a decisive six overs in the match, as the momentum swung in the visitors' favour, despite Selman battling hard to a half-century in 146 deliveries.
As Billy Root played the waiting game early in his innings, getting off the mark from his eleventh delivery and glancing his first boundary off his legs two deliveries later, the fourteenth he faced beat him all ends up, flying off the edge into the hands of Sam Hain at second slip.
Selman, unbeaten on 62, and Callum Taylor, 14 not out, saw the Welsh county through to tea, and they needed a further 187 in the final session, with the visitors requiring a further six wickets.
They moved at a pedestrian pace in the final session, offering little in the way of chances before Taylor fended an uppish delivery from Sidebottom to short-leg after 29 overs at the crease and a partnership of 67.
The visitors had their biggest breakthrough when Hannon-Dalby struck Selman leg-before for 73, the batsman's valiant effort ended after 215 deliveries when he was struck suspiciously high on the leg, and Glamorgan's lower order still had 18.5 overs to bat out.
There was little doubt about Cullen's dismissal, though, as he was dismissed in similar fashion by spinner Alex Thomson for his first wicket of the match. Douthwaite followed soon after, edging a rising delivery from Sidebottom to the keeper.
The visitors edged closer to a victory when Lukas Carey edged Hannon-Dalby to slip, but Michael Hogan and Timm van der Gugten survived the final three overs.
Warwickshire finish the campaign in third place in the group, while Glamorgan are rooted firmly to the bottom. The visitors' attention now turns to the Vitality Blast where they host Glamorgan at Edgbaston on Friday night.