David Hussey’s 81 proved in vain as as Warwickshire Bears ended Notts Outlaws’ winning start in the Friends Provident t20.
Inspired by an opening stand of 74 between Jonathan Trott and Neil Carter, Warwickshire sealed victory with 7 balls to spare.
"Poor fielding has cost us ten runs today and we've dropped two catches and come out on the losing end," said Nottinghamshire Director of Cricket Mick Newell.
"I praise the players when they have played well but we have to be honest with ourselves when we've played poorly.
"We won't wallow in it and we know that we can put things right against Derbyshire tomorrow night but we've seen mistakes today that you can't afford to make in Twenty20 cricket."
Notts remain top of the northern section and will look to bounce back against Derbyshire at the County Ground on Thursday evening.
Having won the toss and batted, Notts slipped to 40-4 before Hussey and Chris Read set about resurrecting the innings.
Read contributed a run-a-ball 26 in a fifth wicket partnership of 88 and after Mullaney’s 3, Paul Franks joined Hussey in targeting the bowling of Rikki Clarke to end the innings on 176-6.
Notts enjoyed a brief flurry to reduce Warwickshire from 99-1 to 124-5 but couldn’t stem the flow.