Middlesex (347-6 dec & 185-3) lead Surrey (282) by 250 runs
First ball of the day at The Oval and Nick Gubbins tucks a single off spinner Dan Moriarty to bring up his second half-century of the match.
It's come off 86 balls and included five fours so far.
Middlesex now 250 ahead as they look to tee-up a Surrey run-chase later.
Let's play!
Getty ImagesCopyright: Getty Images
Right then - eyes down for the start of the final day.
Which side will cross the finish line first and pick up an opening round win?
Stay right here with us to find out.
Northants aim to weather new ball
Northamptonshire (142 & 317-6) lead Warwickshire (369-8) by 90 runs
Andrew Radd
BBC Radio Northampton at Edgbaston
Getty ImagesCopyright: Getty Images
Northamptonshire's third-day batting hero
Charlie Thurston reckons it will be a "big first hour" at Edgbaston
this morning when the visitors resume 90 runs ahead with four wickets in hand.
"They will come hard at us," Thurston
told BBC Radio Northampton. "Hopefully Rosso and Proccy (overnight
pair Adam Rossington and Luke Procter) can weather the second new ball - then
we'll be looking to bat for as long as possible and see how the game goes.
"From the position we were in - at 148 for
five - getting a lead was the first checkpoint. Now we've got to pile on
as many as we can."
Thurston's
knock of 96 - sharing a county record sixth-wicket stand against Warwickshire of 159 with Rossington
- breathed fresh life into a match that had looked set to finish inside three
days.
Listen live!
Every ball of every match in this Bob Willis Trophy opening round is live on the BBC Sport website and app courtesy of our team of BBC local radio commentators.
Find your match of choice by searching through the liver coverage options at the top of the page.
If you're out and about during the day, you can also hear commentary of the final day of Surrey v Middlesex on BBC Radio 5 Live Sports Extra on DAB Digital Radio.
What happened on day 3?
Bob Willis Trophy round-up
We had our first winners in this competition on Monday plus a few other notable performances as sides set up winning positions heading into the final day.
Read Ged Scott's round-up of all that happened below.
Olly Stone, Nick Gubbins, Haseeb Hameed and Ollie Robinson are just a few of the England hopefuls who've stood out in the Bob Willis Trophy so far.
Who do you think is closest to a call-up? Any other names we should mention?
You can give your thoughts on this - and anything else county cricket related - by using #bbccricket on social media.
Yorkshire victory charge set for delay
Yorkshire (199 & 103-3) need 68 more run to beat Durham (103 & 266)
Looking like they'll have to wait a while before starting the final day up at Chester-le-Street with Yorkshire just 68 runs shy of an opening round win...
One last push awaits for the sides in this opening round of the Bob Willis Trophy.
Victory is on the horizon for a few while others may have to show a bit of grit and determination to fend off defeat or indeed, move themselves into a potential winning position.
Eight matches remain after a victory for Sussex against Hampshire yesterday. Who else will be toasting a win later?
Stay with us for full coverage of this fourth day.
Live Reporting
Adam Williams and James Law
All times stated are UK
50 for Nick Gubbins
Middlesex (347-6 dec & 185-3) lead Surrey (282) by 250 runs
First ball of the day at The Oval and Nick Gubbins tucks a single off spinner Dan Moriarty to bring up his second half-century of the match.
It's come off 86 balls and included five fours so far.
Middlesex now 250 ahead as they look to tee-up a Surrey run-chase later.
Let's play!
Right then - eyes down for the start of the final day.
Which side will cross the finish line first and pick up an opening round win?
Stay right here with us to find out.
Northants aim to weather new ball
Northamptonshire (142 & 317-6) lead Warwickshire (369-8) by 90 runs
Andrew Radd
BBC Radio Northampton at Edgbaston
Northamptonshire's third-day batting hero Charlie Thurston reckons it will be a "big first hour" at Edgbaston this morning when the visitors resume 90 runs ahead with four wickets in hand.
"They will come hard at us," Thurston told BBC Radio Northampton. "Hopefully Rosso and Proccy (overnight pair Adam Rossington and Luke Procter) can weather the second new ball - then we'll be looking to bat for as long as possible and see how the game goes.
"From the position we were in - at 148 for five - getting a lead was the first checkpoint. Now we've got to pile on as many as we can."
Thurston's knock of 96 - sharing a county record sixth-wicket stand against Warwickshire of 159 with Rossington - breathed fresh life into a match that had looked set to finish inside three days.
Listen live!
Every ball of every match in this Bob Willis Trophy opening round is live on the BBC Sport website and app courtesy of our team of BBC local radio commentators.
Find your match of choice by searching through the liver coverage options at the top of the page.
If you're out and about during the day, you can also hear commentary of the final day of Surrey v Middlesex on BBC Radio 5 Live Sports Extra on DAB Digital Radio.
What happened on day 3?
Bob Willis Trophy round-up
We had our first winners in this competition on Monday plus a few other notable performances as sides set up winning positions heading into the final day.
Read Ged Scott's round-up of all that happened below.
England hopeful Robinson shines in Trophy
England hopeful Ollie Robinson takes 5-29 as Sussex beat Hampshire by 94 runs to become the first match winners in the Bob Willis Trophy.
Read moreGet Involved
Tweet using #bbccricket
Olly Stone, Nick Gubbins, Haseeb Hameed and Ollie Robinson are just a few of the England hopefuls who've stood out in the Bob Willis Trophy so far.
Who do you think is closest to a call-up? Any other names we should mention?
You can give your thoughts on this - and anything else county cricket related - by using #bbccricket on social media.
Yorkshire victory charge set for delay
Yorkshire (199 & 103-3) need 68 more run to beat Durham (103 & 266)
Looking like they'll have to wait a while before starting the final day up at Chester-le-Street with Yorkshire just 68 runs shy of an opening round win...
Weather outlook
A few showers and thick cloud around parts of the country for this final day that may cause some delays to play.
Matt Taylor from the BBC Weather Centre has the full forecast below.
How it stands on the final day
Eight matches remaining after Sussex's win against Hampshire yesterday in the South Group and here's how they looked at stumps last night.
North group:
Emirates, Chester-le-Street: Yorkshire (199 & 103-3) need 68 more runs to beat Durham (103 & 266)
Trent Bridge: Derbyshire (239 & 129-1) need 236 more runs to beat Nottinghamshire (324 & 279)
Worcester: Lancashire (322 & 96-3) lead Leicestershire (409-8 dec) by 9 runs
Central group:
Bristol: Gloucestershire (267 & 135-3) trail Worcestershire (428-5) by 26 runs
Taunton: Glamorgan (131 & 126-5) need 330 more runs to beat Somerset (296 & 290-8 dec)
Edgbaston: Northamptonshire (142 & 317-6) lead Warwickshire (369-8) by 90 runs
South group:
Chelmsford: Essex (298 & 0-0) need 202 more runs to beat Kent (387 & 112)
The Oval: Middlesex (347-6 dec & 184-3) lead Surrey (282) 249 runs
Welcome along for the final day
One last push awaits for the sides in this opening round of the Bob Willis Trophy.
Victory is on the horizon for a few while others may have to show a bit of grit and determination to fend off defeat or indeed, move themselves into a potential winning position.
Eight matches remain after a victory for Sussex against Hampshire yesterday. Who else will be toasting a win later?
Stay with us for full coverage of this fourth day.