Joe Root marked his first Test outing as England captain by scoring an unbeaten 184 against South Africa, helping his side to 357-5 at the end of day one.

The hosts were languishing on 17-2 at Lord's after losing former skipper Alastair Cook (3) and Keaton Jennings (8) for a combined 11 runs.

Then came a solid showing with the bat from Root, sharing a big-scoring partnership with vice-skipper Ben Stokes and Moeen Ali to get England back on track, but only after being dropped on 16 runs.

Gary Ballance (20), Ben Stokes (56) and Jonny Bairstow (10) also fell, the latter being removed by Vernon Philander after he had earlier taken both England openers.

Root's tally was the highest by an England player in their first game in charge, joining his three predecessors in marking the occasions with a Test ton.