We are up and running in our 19:00 BST matches now and Hashim Amla has settled in nicely for Derbyshire as Yorkshire's Jack Brooks goes for 12 in his first over. The away side are 25-0 after three overs, with Amla on 18.

Joe Denly has also started sharply sending Steve Magoffin for a four and six, but Oliver Robinson has Daniel Bell-Drummond caught behind for one with his second ball to leave Kent 16-1 off their first two overs.

However, Hampshire openers Michael Carberry and James Vince have started off rather watchfully against the Essex bowlers, with just one boundary in their opening two overs to take them to 8-0.

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Varun Chopra reverse sweeps Samit Patel for four and then lofts him over the covers for another boundary. The Birmingham skipper onto 42 and holding this innings together.

Ebony Rainford-Brent
Ex-England batter on BBC Test Match Special

"Samit Patel is an excellent player in this format. He brings a lot with the bat and ball, and he'll always be in the game."

Steven Mullaney's second over is another tidy one. Six runs from it, 0-10 off his two. And another spinner about to come on, as Samit Patel spins himself a couple of catches before preparing to bowl.

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Luke Fletcher strikes again, for the second time in the over, as Rikki Clarke attempts to smear him over mid-wicket and instead drags onto his stumps. BBC Radio 5 live sports extra's Charles Dagnall says Birmingham are "in a pickle" and it's hard to disagree with him. Laurie Evans joins his captain Varun Chopra at the crease.

James Franklin may have to put some of his wages towards repairing a fan's car as he hits the final ball of the Middlesex innings for a massive six into the parking area at Bristol as they post 169-3 off their 20 overs against Gloucestershire.

After losing an early wicket, Leicestershire raced along with Ned Eckersley making 29 off 14 balls, hitting four fours and six, before being caught at mid-wicket off Lancashire's Steven Croft to leave his side nice poised on 64-2 off six overs.

South African batsman Colin Ingram has struck paceman Tom Curran for two sixes as Glamorgan raced to 57-1 off their first six powerplay overs.

And, there is early joy for Durham as Chris Rushworth claims the vital wicket of David Willey, who departs for a first-ball duck caught by John Hastings at gully, to leave Northants 8-1 after one over.

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Luke Fletcher with a beauty! And Tim Ambrose is on his way back to the pavilion. Or the dugout. Whatever they have in the T20 Blast these days. Ambrose has no chance as a yorker beats his bat and rattles the timber behind him. Rikki Clarke is the new man in. Notts definitely on top. Jonathan Trott, not playing tonight, can only watch on glumly.

Birmingham Bears pass 50 in the eighth over, off-spinner Steven Mullaney going for just four off it.

BBC Radio Northampton's Chris Egerton: "Just 28 runs taken off the last 5 overs by Durham. Northants not without a chance. But still tough chase."

Luke Fletcher replaces Harry Gurney and goes for five runs in his first. Varun Chopra is 28 not out off 21 balls.

BBC Coventry & Warwickshire's Clive Eakin at Trent Bridge:

"Varun Chopra and Tim Ambrose are leading the Bears' opening defence of their title after a difficult start at Trent Bridge."

BBC London's Kevin Hand: "First 6 of innings comes in penultimate over, despite Middx's strong showing with the bat - again that tells story about pitch."

Live commentary of Gloucestershire's run chase can be heard via the Live Coverage tab.

Welcome to the T20 Blast, Vernon Philander. The South African seamer is despatched through the covers twice by Tim Ambrose, and then plonked through mid-wicket for another boundary. So 14 off the over, and the powerplay ends with Birmingham 41-2.

Yorkshire are one of the few teams in action tonight without an international player, with Australia's Glenn Maxwell joining them next week and Aaron Finch still injured. Jonny Bairstow is in rich form at the moment after scoring a century in the County Championship, while Liam Plunkett returns to boost the bowling attack. For Derbyshire, Hashim Amla will open alongside Wes Durston. Amla has made 600 international T20 runs, in just 26 appearances.

Yorkshire Vikings: Gale (capt), Hodd, Lees, Bairstow, Leaning, Pyrah, Rashid, Bresnan, Plunkett, Brooks, Fisher.

Derbyshire: Durston (capt), Amla, Hughes, Thakor, Elstone, Godleman, Hughes, Poynton, Wainwright, Cotton, Footitt.

Yorkshire have won the toss and will bowl first - live commentary via the Live Coverage tab.

Hampshire, one of the form teams in limited-overs cricket over the past few years, have veteran batsman Owais Shah in their side for the home game against Essex. The visitors are skippered by Ryan ten Doeschate, who has flown back from the Indian Premier League for the game, and their attack is spearheaded by Australian fast bowler Shaun Tait.

Hampshire: Carberry, Vince (capt), Adams, Shah, Ervine, Smith, Wheater, Wood, Arafat, Briggs, Edwards.

Essex: Ryder, Browne, Smith, Yen Doeschate (capt), Velani, Foster, Napier, Masters, Tait, Taylor, Malik.

Hampshire have won the toss and decided to bat first - live commentary via the Live Coverage tab.

BBC Sport's Elizabeth Ammon: "Warwickshire have started in whatever way the opposite to like a rocket is."

BBC local radio and Radio 5 live sports extra commentary from Trent Bridge, and indeed all of today's T20 Blast games, can be found via the Live Coverage tab.

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A little escape for Varun Chopra, who is deceived by a Harry Gurney slower ball and he chips into the covers, away from a fielder though. Chopra picks up two, then picks up another four with an on-drive. And then he almost plays on! An eventful over.

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Nick Compton passes his previous T20 high score of 74, before missing a straight one from Gloucestershire's James Fuller and is trapped lbw leaving Middlesex 151-3 off 18 overs.

There are two wickets for Shahid Afridi, his first in a Northants shirt as Durham stuttered to 174-8 from their 20 overs, following a fast start. The Jets lost their last four wickets for just 21 runs. With rain slightly coming down at Chester-le-Street, the away side will be hoping to get in the five overs they need to make it a game.

Leicestershire have started all guns blazing against Lancashire as Mark Cosgrave sends George Edwards for a four and then a six, with the away side 21-0 off two overs.

And, Mark Wallace falls early on for Glamorgan, having hit Matt Dunn for two fours in the first over of the innings as Surrey's Tom Curran has him caught by Wahab Riaz for 10. Glamorgan are 18-1 off three overs.

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Even at this early stage, much could depend on Birmingham's Varun Chopra. The Bears skipper hits Jake Ball for three fours in the over, the second of them a superb drive through the covers.

Ebony Rainford-Brent
Ex-England batter on BBC Test Match Special

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"Excellent ball from Harry Gurney. Some really good late movement. He's been bowling back of a length but he noticed that Tom Lewis was a bit vulnerable. He pitched it up and got the swing, and Tom Lewis was nowhere to be found."