Moores gutted as defeat for Nottinghamshire at Warwickshire opens up group
Set a victory target of 309 in 74 overs, the visitors were bowled out for 138 with eight overs to spare as spinner Danny Briggs followed up his important runs in the match with a decisive spell of 24.3-14-36-4.
After the Bears took their overnight 201 for six to 264 all out, they bowled with collective skill to close out a thrilling victory.
At 89 for five, Nottinghamshire had no choice but to abandon their quest for victory and their hopes of defending out for a draw were scuppered as the Bears maintained the pressure with disciplined bowling.
"We feel absolutely gutted. They bowled well but I think , in some ways, we caused our own demise a little bit, but we have got to dust ourselves down and come back strong against Essex next week.
Moores said: "It was a tight game all the way through. Probably the key time was the third day when they played really well but we managed to stay in the game.
"Then we cleaned them out this morning to leave all three results possible but I think we got a bit distracted by looking for the win a little bit when we first started batting and made some mistakes."
In the morning, Burgess and Briggs took their partnership to 103 in 33 overs before the former top-edged a sweep at Liam Patterson-White to slip. Craig Miles was soon run out by Ben Slater's direct hit, before Fletcher rattled the stumps of Briggs and Liam Norwell.
Norwell then soon struck with the ball as Haseeb Hameed edged to wicketkeeper Burgess and two big wickets fell in successive overs when Ben Duckett and Ben Slater were dismissed.
A stumping by Burgess off seamer Olly Hannon-Dalby dismissed Joe Clarke, before Steven Mullaney was out to leave Notts at 89/5.
Lyndon James and Tom Moores ate up valuable time in a stand of 16 overs, but both fell in quick succession to leave Nottinghamshire on the brink.
Patterson-White's 72 minutes of defiance ended rather unluckily when a defensive shot off Miles dropped the ball back on to the stumps.
That left numbers ten and 11 with 11 overs to survive - and they managed just three before Fletcher was bowled to the delight of the crowd.