England 373-3: Buttler hits England's second-fastest century in ODI cricket - off 50 balls
Morgan adds 71 off 48 balls, Roy makes 87 on return from injury
Fakhar hammers 138 off 106 to give Pakistan chance of victory
Willey impresses with ball - taking 2-57
Roy 75, Root 18
Jason Roy walks down the pitch and punches back through mid-on for a single.
Joe Root then deftly guides to third man for a single.
Faheem Ashraf tries to rush Roy with a short ball but the Surrey man gets on top of it to roll it out to deep mid-wicket for one more.
Root clips the last ball out to the deep on the leg side for a single. That's exactly 150 and six an over for England off the first half of their innings.
Here's the only wicket of the day so far, when Pakistan broke up England's opening pair.
Fakhar Zaman took the catch to dismiss Jonny Bairstow at the second attempt.
A single each for Roy and Root to finish the over - nine from it.
Charles Dagnall
TMS commentator
Again, it's minimal effort and excellent execution of the shot from Jason Roy.
Jason Roy goes in to out and heaves Yasir Shah out over extra cover.
That hits the rope on the full and that's six! Sublime.
Charles Dagnall
TMS commentator
At first I thought that was just going to be a couple of runs, but the timing was sweet from Jason Roy. It's the type of shot that bowlers slump their shoulders and exhale deeply at.
Run rate 5.91
Nagging lines from Faheem, with Roy and Root moving about the crease and down the pitch to try and fashion something.
Roy then stays put and clips a ball slightly back of a length firmly through mid-wicket with an angled bat.
Two is the call but he's hit that so well it zips away for four.
Faheem Ashraf is coming back into the attack, replacing fellow opening bowler Shaheen Afridi...
Ramiz Raja
Ex-Pakistan captain on TMS
Pakistan will be reasonably happy in that they've kept England's run rate under six, especially on a pitch as good as this.
Allow Twitter content?
This article contains content provided by Twitter. We ask for your permission before anything is loaded, as they may be using cookies and other technologies. You may want to read Twitter’s cookie policy, external and privacy policy, external before accepting. To view this content choose ‘accept and continue’.
Roy 61, Root 11
Shot! Width from Yasir Shah and Joe Root expertly finds the gap behind backward point with an angled bat. That's four!
Root then bends down to sweep firmly around his front pad for a single.
Image source, Reuters
Stephan Shemilt
BBC Sport at The Ageas Bowl
Here is the most disappointed man in Southampton. Where once the TMS box had a double bed, now Tuffers has to make do with feet on the table. He's considering lying on the floor....
Joe Root punches nicely down the ground but the lanky Shaheen Afridi gets down well to prevent the boundary.
Four dot balls in a row before Root clips through mid-wicket for one.
And Jason Roy does the same off the last.
YJB is gone but JRoy remains...
Root and Roy taps two singles apiece off Yasir.
England are just short of six an over after the first 20 overs of their innings.
Image source, Getty Images
Andy Zaltzman
Test Match Special statistician
Jonny Bairstow hit 51 from 45 balls with six fours, five off which came off Shaheen Afridi who dismissed him. It's his 15th score of 50 or more in one-day cricket.
Joe Root is in at three. The Test captain will look to be positive and keep the scoreboard ticking along, while perhaps letting Jason Roy hit the big blows.
Can Pakistan build on that breakthrough? England still firmly on top here.
Michael Vaughan
Ex-England captain on TMS
It goes fast, it's quite high, and he does well to not carry his momentum over the rope. What a tremendous catch.
Simon Mann
TMS commentator
He's caught it on the second attempt! Jonny Bairstow made decent contact with that and it might well have gone for six, had it not been intercepted.
Image source, AFP
Bairstow c Fakhar b Shaheen 51 (Eng 115-1)
No, Jonny Bairstow cannot convert.
The England opener tries to pull a short ball from Shaheen Afridi into the stands but doesn't quite get hold of it and Fakhar Zaman is in play at deep square leg.
The Pakistan batsman dives two-handed, gets there, spills it, but then clings on at the second attempt. A superb catch in the end.
And a fine knock from Bairstow comes to an end just when he was really getting going.