Nottinghamshire 162 for 7 (Patel 58, Read 35*) beat Yorkshire 160 for 7 (Head 40, Lyth 39, Gurney 3-16) by three wickets
Nottinghamshire may be looking over their shoulders somewhat anxiously in the Championship but their white-ball game is gathering momentum, so much so that their place in the quarter-finals of the NatWest Blast is all but assured with two matches remaining.
Their last 10 matches in this competition have included four washouts, more than any other side, yet they have won all of the other six, this one added to the sequence with two balls to spare.
After Yorkshire had posted an under-par 160, which was in no small part down to the disciplined bowling of Harry Gurney and Luke Fletcher in particular, Samit Patel's 58, the highest score of the night, was the crucial innings.
Even then, however, Patel's dismissal in the final over after two Liam Plunkett dot balls caused nerves to jangle before Chris Read drew a deep breath and cracked the winning boundary through square cover.
It left Yorkshire's qualification hanging by a thread, with the probability that they will need to win their three remaining matches to be sure to go through, and Alex Lees, in his first season as captain, was in no mood to take the rough with the smooth, claiming that a contentious umpire's decision cost them the match.
It came in the fifth over of Nottinghamshire's chase for their 161-run target, when umpire Martin Saggers called no ball for a fielding irregularity, namely that Yorkshire had one too many players outside the circle.
Plunkett was bowling to Dan Christian, who ran a single off the no ball. Greg Smith then hit a four from the free hit before Christian swung through the last ball of the over - the extra one in Lees's eyes - to score six.
"We could have done with 10 more runs with the bat and saved 10 in the field, and then we'd have won," Lees said. "But even with that score it's boiled down to a terrible decision by the umpire. I don't know how, from 40 yards away, you can tell if someone is in or out of the ring, and it's cost us 12 runs.
"It was judged that I was out of the ring. I wasn't out of the ring, and it cost us 12 runs. I think even if someone is out by a yard, can you see that from 40 yards? He said that he watched the bowler from his run-up all the way and said he watched me all the way.
"I don't think he's doing his job properly if he's looking at me when the bowler's bowling. I don't how he can track it. I don't know how he can track all seven players in the ring.
"Sometimes in cricket they go your way, and unfortunately it went for Notts tonight."
Although emotions run high sometimes in cricket, the comments by Lees were unwise and it would be a surprise if he does not have to account for them with the authorities, given their tough stance on dissent.
Mistakes are sometimes made. Later in the innings, for example, Nottinghamshire's Steven Mullaney had grounds to question how he could be given run out with the naked eye - again by Saggers - when he appeared to have beaten Steve Patterson's direct hit to the non-striker's end when Patel sent him back.
That could have been a turning point. At that moment, Nottinghamshire were 59 short of their target, with 53 balls left and some restrictive overs by the Yorkshire spinners, Adil Rashid and Azeem Rafiq, seemed to be tipping the balance in favour of the visiting team.
In the event, Patel and Read stepped on the accelerator when Patterson and Tim Bresnan returned, plundering 39 runs in three overs so that three runs were needed off the final six deliveries, in which Nottinghamshire were always likely to get at least one hit off the square.
Read finished on 35 not out and Greg Smith's 32 off as many balls was essential in providing an anchor after Michael Lumb and Riki Wessels failed. Yorkshire's fielding, on the whole, was excellent.
Yorkshire, who had won their last three matches batting first, again backed themselves to set a target they could defend and although Lees was an early casualty, Adam Lyth was in superb touch, the format requiring a change of gear from his double century against Surrey in the Championship but inhibiting him not one jot.
Lyth raced to 39 off 20 deliveries, the last 18 of them coming in one dreadful over from Nottinghamshire captain Christian that also conceded five wides. But then Patel, whose own opening over had cost 12 runs, had some revenge when Lyth tried to clear the rope again in the seventh over but, with the field now back, found Imran Tahir on the cover boundary.
The left-handed England batsman, whose form this season is being talked about in selectors' meetings again, gave way to Travis Head, the 22-year-old Australian left-hander, whose debut innings for Yorkshire looked to have set up his new side for a total perhaps in the 180 to 220 range.
Head, who made a T20 hundred off 53 balls for Jason Gillespie's Adelaide Strikers in the Big Bash last December, introduced himself by hitting four sixes in a 25-ball blitz that brought him 40 runs, doing most of the damage between the 10th and 12th overs as he launched in turn into Imran Tahir, Patel and Mullaney.
He had some luck. Dropped by Patel at long-on off Mullaney on 30, he was fortunate twice more when steepling top-edges fell safely to ground. His luck ran out when the excellent Gurney returned to have him caught at long-on by Riki Wessels.
Head's partnership with Kane Williamson added 67 in 42 deliveries but with the Australian's dismissal in 14th over went Yorkshire's momentum. Indeed, there were only two boundaries scored in the last eight overs of the innings and just 38 runs added after Head was out.
Nottinghamshire's bowling was top class. Mullaney dismissed Williamson when a paddle-sweep from the Kiwi found Imran Tahir lurking round the corner and both Gurney and Fletcher did their jobs superbly at the death, giving away only 13 runs between them in the final three overs. Yet Yorkshire's batting lacked something in finesse.