Root stumped on 149 off a no-ball; also dropped on 16
Skipper shares in big stands with Moeen (61*) & Stokes (56)
Three wickets for Philander
England won toss; first of four-match series
Graeme Smith
Ex-South Africa captain on BBC Test Match Special
You're going to make a lot of mistakes as captain but you have to find something that works for you. It took me about three or four years to grow into the role. At 26 that was the kind of age I found the things I thought we needed. In the early years it was just determination and the runs I scored that allowed people the patience to stick with me.
To be fair, if you are an England fan you will be used to these kind of top-order shenanigans. I think we all hoped, though, that a change of captain and a few months away to refresh all things Test would perhaps bring a new solidity.
Thankfully, Joe Root remains as good as ever. Captain's innings anyone?
Afternoon everyone. Well, that went well...
BBC Test Match Special
Anyway, the collapse has rather overshadowed Joe Root's first morning as England Test captain. Nevertheless, Test Match Special will be discussing Root's early years during the lunch break in the company of his father Matt and grandfather Don.
I'm off for a little while, Phil Dawkes will keep you company through the break.
#bbccricket
Greg Double: Really clever work from England. Forcing Root to make a textbook "captain's innings" on day one is a great initiation.
What to make of all that? The new England looks a lot like the old England to me. The clock is ticking to find the right top order for the Ashes.
Tom Fordyce
Chief sports writer at Lord's
If Joe Root had any illusions about the challenges ahead, that first session of his Test captaincy will have removed them. New skipper, old problems: a weakness at the top of the order, an issue at three, a foldability continuing down the order.
Graeme Smith
Ex-South Africa captain on BBC Test Match Special
There was a lot of uncertainty coming into this match for both teams, Anderson injured, Ballance back, Faf du Plessis not here, Elgar making his debut, no-one really knew which way it would go. It has been a wonderful morning for South Africa having lost the toss.
Eng 82-4
Philander hurries in, twice Root's pads are in danger, a single leaves Stokes with two balls to survive. A big stride to defend, then a push back down the pitch. The players head for the pavilion. South Africa have bossed the first session of this series.
Graeme Smith
Ex-South Africa captain on BBC Test Match Special
There was a lot of uncertainty around Philander carrying an injury. The thing about him is he is always at you. It kind of floats through the air but when it pitches seems to generate pace.
Can Joe Root drag out this Maharaj over so that Philander doesn't get another one before the break? Pull away from the stance, sweep a single. Now South Africa dawdle. The clock ticks closer to the top of the hour. They'll sneak one more in. Vernon Philander prowls again...
Graeme Smith
Ex-South Africa captain on BBC Test Match Special
Dean Elgar in his first session couldn't have asked for more. His bowlers have stepped up and bowled superbly well. The only thing they are not on top of is the over-rate, which has been a bit slow, though we have had four wickets.
Philander 7-1-25-3
The replay shows that it would have hit the top of middle stump, umpire's call on review. Ben Stokes is the new man. A couple of years ago, he and Root blasted England out of a hole against new Zealand. Now they are skip and vice-skip.
Image source, Getty ImagesGraeme Smith
Ex-South Africa captain on BBC Test Match Special
Wonderful bowling, the batsman caught on the crease. He was moving the ball both ways and Bairstow was not moving his feet, almost uncertain in his movement. Almost crab-like batting from the top order and they have allowed South Africa to bowl. Root is the only one showing intent going forward and back.
Bairstow lbw Philander 10 (Eng 76-4)
Four down! Jonny Bairstow is absolutely plumb and England are in tatters. It's that man Vernon Philander again. He gets one to hold its line, maybe nipping up the slope and Bairstow is trapped on the crease. The finger is up quickly, Bairstow doesn't even think about a review. On the first morning of this series, England are teetering on the ropes.
Michael Vaughan
Ex-England captain on BBC Test Match Special
I think in my first Test as captain I was caught at fine-leg playing the exact same shot as Root, a top-edged pull! Four of five got out to it in that innings and the story was that because it was my favourite shot I'd told all the others to play it.
Maharaj isn't a big turner of the ball. Shaven-headed, he delivers the ball from round the wicket, wide of the crease, with no great flight. This Yorkshire pair run well, finding singles where they probably shouldn't.
Geoffrey Boycott
Ex-England batsman on BBC Test Match Special
People who saw Joe this morning said he was nervous but that's OK with me, it means he cares. What you have to do is handle your nerves. You want to do well but you have to just handle it.
Root 30, Bairstow 8
Vernon Philander, two wickets earlier on, returns for a pre-lunch burst. There are plenty of empty seats behind him at the Nursery End, perhaps a few already popped off to the champagne tent. Root belts the ground with his bat, then turns through square leg for four. Skittish from Root today. Two chances, some nice strokes.
Graeme Smith
Ex-South Africa captain on BBC Test Match Special
When you only have three seamers your spinner is key and Dean Elgar will be hoping Maharaj can give him some control.