Yorkshire make record 227-5 & beat Notts
Surrey beat Essex by two runs
Birmingham Bears beat Worcs by eight wickets
Buttler hits 59 off 39 balls for Lancs
Wins for Lancs, Hants & Derbys
Glos & Middlesex tie early game
As well as Surrey's dramatic win at Chelmsford, there were opening-night wins for Lancashire Lightning, Hampshire and Derbyshire Falcons, while the Birmingham Bears also beat Worcestershire Rapids by eight wickets in the West Midlands derby.
Earlier, Gloucestershire and Middlesex produced a dramatic tie.
It's been a cracking night, after another good day in the Test match for England. Join us again next time for some more T20 Blast action.
That just about concludes tonight's T20 Blast action.
Let's just round up all the other results for you...
Result: Essex 186-6 v Surrey 188-8
Image source, Rex FeaturesYou have to say, both Curran brothers were superb tonight.
Surrey skipper Jade Dernbach is delighted. They've got their campaign off to a terrific start.
Ravi Bopara's 75 from 46 balls for Essex wasn't enough.
Essex 186-6 v Surrey 188-8
Paul Walter swings and misses and Surrey win!
Excellent bowling from Tom Curran in the final over and the visitors snatch it. Excellent cricket.
Image source, Rex Features
Essex 185-6 v Surrey (target 189)
Ashar Zaidi is gone! Four runs needed from the final ball.
From the previous ball, Surrey thought they'd run out Zaidi but it was not out - he'd just made it.
Out comes Paul Walter to face the final ball of the match...
Three to tie.. Four to win.
Essex 183-5 v Surrey (target 189)
James Foster tries to scoop Tom Curran's delivery towards the boundary but doesn't make contact.
A bye is given. Three balls left. Seven runs needed to win.
Essex 181-5 v Surrey (target 189)
Essex need eight to win... but Ravi Bopara's gone! It's a cracking yorker and - more importantly - a dot ball.
James Foster comes out for Essex - can he be the match-winner?
Eight to win, from four balls. This is pressure.
Image source, Rex FeaturesEssex (179-4) need 10 to win from six balls
Ravi Bopara steps up and takes this match on all by himself as he smacks Jade Dernbach for back-to-back maximums.
He adds a single from a full toss to put Essex within 10 runs over victory - with one over left.
If the visitors win this, was this the moment the game swung in Surrey's favour? Watch it back, as Sam Curran took the wicket of Ryan ten Doeschate.
Essex 164-4 v Surrey (target 189)
Image source, Rex FeaturesTom Curran bowls the 18th over and starts nicely, with a useful dot ball, but then Ashar Zaidi smacks one away, high for four - not quite a six.
Then another dot ball comes thanks to a slower delivery from Curran, before Ashar Zaidi finds another boundary and they take two to close the over with 11 runs taken from it.
So 25 now needed from the final two overs. It's become extremely tense!
Essex 153-4 v Surrey (target 189)
Surrey skipper Jade Dernbach brings himself back on to bowl.
He concedes four runs, and then bounces one into Ashar Zaidi's body and - as it falls away - tries to kick the loose ball along the ground into the stumps, but his kick slides wide.
Then an inside edge bounces away for four runs for Ravi Bopara. Another inside edge takes Essex up to 153-4. It's not a bad over from the Surrey skipper, in the end.
Three overs left. Target rate: Still 12 per over.
Essex 141-4 v Surrey (target 189)
After a no ball, Ashar Zaidi gets a free hit, from which Essex take a single.
Two per ball is what they need now or - in old English - 12 an over.
Essex 136-4 needing 53 runs from 26 balls
Excellent bowling from Sam Curran and, after two dot balls and a two, Ryan ten Doeschate cracks.
He's plumb, lbw, for 25. In comes Ashar Zaidi...
Image source, Rex FeaturesEssex 134-3 v Surrey (target 189)
Ravi Rampaul bowls a couple of very decent yorkers and he concedes only five runs from the over.
Essex's Ravi Bopara has 51 from 34 balls so far.
Meanwhile, you can watch Bopara's earlier six off the bowling of Rampual here:
Essex 131-3 needing 58 to win from 34 balls
"Ohh, Ravi Bopara" rings out at Chelmsford as the hosts salute Ravi Bopara, as he moves onto 50.
Essex 129-3 v Surrey (target 189)
Image source, Rex FeaturesOh no! Surrey's Ollie Pope's getting some stick from the Essex fans now, as he completely misses the ball fielding out towards the boundary and his error lets Ravi Bopara's guided stroke bounce over for four runs.
Ravi Rampaul will return to the bowling next... Essex need 60 to win from 36 balls.
Essex 119-3 v Surrey (target 189)
A much better over in the field for Surrey, as Sam Curran keeps things a bit tighter and just eight are conceded.
But this partnership for Essex is now looking crucial. Ryan ten Doeschate and Ravi Bopara have added 44 runs from 3.5 overs.
Essex 105-3 v Surrey (target 189)
The home crowd are enjoying themselves at the moment.
Ravi Bopara is playing risky cricket, but he's getting away with it.
He finds another big six over square leg, after swinging one away for four earlier in the over, and 14 are added.
Image source, Rex FeaturesAround the grounds
Image source, Rex FeaturesYorkshire Vikings' gigantic score of 227-5 proved too many for Nottinghamshire Outlaws, who made 179-8 from their 20 overs.
A similar win for Lancashire Lightning against Durham Jets, with the home side finishing short on 140-7, in reply to Lancashire's 192-6.
Shahid Afridi starred in Hampshire's win over Glamorgan in Cardiff, taking 4-20 to restrict the hosts to 145-9 from their 20, defending 167-5.
Finally, Derbyshire Falcons were the only side of the four games to successfully chase. They made 180-3, with Luis Reece making 75 not out, to better Northants Steelbacks' 179-6.
Essex 97-3 v Surrey (target 189)
Ravi Bopara gets a six when it looked like he'd be caught on the boundary. Then Jason Roy later saves a couple of runs on the boundary. But four leg byes were conceded in the over too, so it's a costly one - 16 taken from the over.