Pakistani tail-ender Danish Kaneria hit two runs off the last ball to ensure Essex tied their Twenty20 Cup match with Hampshire in a thrilling finish at the Rose Bowl.
Chasing Hampshire's 164 for six, Essex went into the last over from Billy Taylor needing 11 to win.
A crowd of 7,500 endured the tension of Taylor's last over in which David Masters struck a four to leave Kaneria needing to score three runs from the last ball of the innings to ensure an Essex victory.
Kaneria struck the ball to mid-wicket, the ball bouncing just in front of Michael Carberry as Masters and Kaneria scampered two important runs.
Essex and Hampshire now meet in the final match of their South Division campaigns at Chelmsford on Friday to help decide who qualifies for the quarter-finals.
Hampshire made a sedate start after their captain Nic Pothas decided to bat and managed only 52 for two from the first 10 overs before an acceleration left Essex to chase a demanding total.
Hampshire scored 112 from the next 10 overs in an innings which included six sixes, two of them to Sean Ervine and two more to Michael Brown.
But top scorer was Carberry who overcame a slow start to make 51 from 42 balls, including a six and four fours before he was run out by Graham Napier.
Last night, Napier struck a world-record 16 sixes in an unbeaten 152 against Sussex and this time he was responsible for the early wickets of Michael Lumb and Chris Benham to finish with figures of two for 35.
Essex also found scoring difficult when it was their turn, most of all against South African Nantie Hayward who conceded only 21 from his four overs.
Jason Gallian was Essex's top scorer with 55 before he was the first of two run-out victims at the hands of substitute fielder Liam Dawson.
The turning point appeared to be in the 14th over, bowled by Hayward, when Gallian was run out and next ball James Foster was snapped up at mid-wicket.
But Essex refused to give up, needing 18 off the last two overs and keeping their nerve as the tension mounted.
In the penultimate over, from England's Chris Tremlett, only seven runs were scored and Essex lost Grant Flower and James Middlebrook to leave the pressure on Kaneria and Masters to score the winning runs.
But the ninth-wicket pair struck 10 runs from the final over to ensure each side picked up one valuable point.