Essex enjoyed an entertaining ten-run victory over Somerset at Taunton, which was only soured by an injury to star man Ryan ten Doeschate.
All-rounder ten Doeschate top scored for Essex with a brisk 48, but he was forced to retire in the 17th over with what was later to be confirmed as a torn calf muscle.
He still helped Essex get up to 177-7, which did not look enough as Somerset reached 122-2 in the 13th over, but the hosts suffered a big collapse and they could only muster 167-9 in the end.
Both teams have now won two games and lost three in the South Division and will need to improve to feature in the quarter-finals.
The Essex innings was given a brisk start by Alastair Cook after they had won the toss. The England opener hit four fours in facing only nine balls before sweeping a ball from Zander de Bruyn straight to James Hildreth at short fine leg.
Ravi Bopara fell cheaply, but Matthew Walker hit four fours and a six in his 35, while ten Doeschate looked in supreme touch from the start of his innings and looked set to lift his side towards 200 as he took successive sixes off Arul Suppiah.
It was a massive blow for the Eagles when he collapsed attempting a quick single off Kieron Pollard with the total on 148 for four in the 17th over.
Alfonso Thomas (3-24) took the wickets of Grant Flower and Tim Phillips in a typically tight last over to keep Essex below 180.
That did not look like being enough when Marcus Trescothick (40) and Nick Compton put on 99 in 11 overs, or when Kieron Pollard came in to blast three sixes in the space of four balls off Kaneria. But he was out in the same over and Essex sensed their chance.
Compton was out hit-wicket trying to reverse sweep Masters, having faced 55 balls and hit 11 fours, but at 147-4 the home side still looked favourites.
But David Masters, Scott Styris and Chris Wright had other ideas at the death, bowling full and running through the middle and lower order.
It was later confirmed that ten Doeschate had suffered a torn calf muscle that is likely to keep him out for six weeks.