Yorkshire make 263-9 from their 50 overs
Gloucestershire reach target with three overs to spare
Glos captain Michael Klinger hits unbeaten 137
Surrey play Notts in Monday's semi-final
This is only Adam Lyth's second appearance in the One-Day Cup this season and he is gifted two runs by a poor mis-field at mid-wicket before dabbing a short-of-a-length delivery from Liam Norwell down to third man for a single to end the over.
Jack Russell
Ex-Gloucestershire and England wicketkeeper on BBC Radio 5live
Quote MessageYorkshire have taken this game by the scruff of the neck so early on that Gloucestershire need to take a wicket or two now to get themselves back into this game.
So that's two dropped catches so far by Gloucestershire, both of them tough ones - how costly will they prove? David Payne continues and finally Lyth's judgment of line and length errs as he attempts another flashing drive but sees the ball just miss the outside edge of his bat.
Richard Blakey
Ex-Yorkshire and England wicket-keeper on BBC Radio 5live
Quote MessageYou can see Adam Lyth is quality player, he has shown that in the last couple of years for Yorkshire. Unfortunately for one reason or another he didn't score the runs he wanted to during the Ashes series. That can happen at international level, especially against quality bowlers like the Aussies.
After his let-off from the previous delivery, Alex Lees slices away for three and partner Adam Lyth then collects his eight four so far as Yorkshire maintain their momentum.
Yorkshire 52-0 (Lyth 41, Lees 2)
Alex Lees attempts a flashing drive off Liam Norwell, but Michael Klinger is unable to hang onto a difficult diving chance to his left at slip.
A leg glance by Adam Lyth keeps the boundaries flowing for Yorkshire and takes their total to 50. No sign of a four yet from Alex Lees, who is twice beaten by David Payne as he attempts first an off-drive and then a pull shot to a delivery which isn't really short enough.
Following on from the earlier news about Shane Watson's retirement from Test cricket, Australia coach Darren Lehmann and spinner Nathan Lyon have passed on their congratulations.
Meanwhile Test Match Special producer Adam Mountford has had his say, with a little nudge to Watson's reputation for appealing against lbw decisions...
First bowling change by Gloucestershire as Liam Norwell comes into the attack. His opening delivery costs four leg-byes off Adam Lyth's thigh pad and the left-hander then clubs him away emphatically over mid-wicket for a boundary. Gone are Lyth's cares and woes from the Test series in Australia, looks like he's enjoying himself out there.
Strange to see former England wicketkeeper Geraint Jones fielding at long leg, but it's just as well he is as David Payne strays onto Adam Lyth's pads, only for Jones to keep Yorkshire to a single.
Alex Lees is still to find his timing and that's a much better over for the men for Gloucestershire, with just one run off it.
James Fuller starts his third over and is greeted with a lofted drive by Adam Lyth which runs away for four, the Yorkshire opener holding the position to emphasise how satisfied he is with the stroke.
Lyth repeats the dose from the next delivery with a superbly-timed drive along the deck through extra cover, and then shows he can do it off the back foot too as Fuller concedes 14 from the over.
A much tighter over from David Payne yields only a couple of singles, but Yorkshire will be satisfied with their start so far.
Jack Russell
Ex-Gloucestershire and England wicket-keeper on BBC Radio Five-Live
Quote MessageGloucestershire have never performed when they have played on the TV in the last 10 years and they have certainly had a nervy start.
We'll take you away from the action at Headingley for just one moment as we've got some big breaking news for you - Australia's Shane Watson has called time on his Test career with immediate effect.
The 34-year-old, who sustained a calf injury in Saturday's one-day victory over England, played 59 Tests for Australia, scoring 3,731 runs and taking 75 wickets.
But he only played the first Ashes Test in Cardiff this summer before being replaced by Mitchell Marsh.
More on that when we get it.
Yorkshire skipper Alex Lees hasn't seen much of the strike so far, but he is off the mark with a single to third man. After a prolific season in 2014, the 22-year-old has found runs harder to come by this summer. He has only managed one century in all competitions so far - but will today be his day?
Lyth has a slice of luck off the final ball as Howell leaps to try and pull off a one-handed catch at point, but can't hold onto a difficult chance.
One Yorkshireman who isn't playing today is England's Joe Root, but he still has a message for his team-mates...
There's a touch of early swing for left-armer David Payne, but he overpitches and Lyth cracks the ball away through the covers for four.
The final ball of the over is wide outside the off stump and Lyth slices over the in-field, but is denied another boundary by the fielder at deep backward point.
How do you feel about Lyth? Is his time up in the England Test squad, or should the selectors keep faith with him for the upcoming series against Pakistan in the UAE? Let us know via #bbccricket
Adam Lyth had a miserable time for England in the Ashes series against Australia - at least from a personal form point of view - but he's soon under way with a boundary, deflecting James Fuller's second delivery down to third man.
Fuller has taken 12 wickets in the competition for Gloucestershire to help them reach the semi-finals, but his radar is off as he gives away three wides down the leg-side in the first over.
It certainly looks like it's perfect weather for cricket on a lazy Sunday morning.
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