Key all-rounder Stokes, who hit his second one-day worldwide century as England took an unassailable 2-0 series lead over South Africa at the Ageas Bowl on Saturday, has managed to bowl only five overs in two matches this past week.
One worry for England ahead of the looming Champions Trophy starting on Friday is that Stokes managed to bowl only three overs in the South African innings having injured his knee in the first ODI win, but he remained on the field.
Miller finished unbeaten on 71 (51 balls, 5 fours and 2 sixes) and Morris on 36 (22 balls, 3 fours and 2 sixes) as the pair shared a partnership of 62 for the sixth wicket in 6.3 overs.
Irrespective of which 11 team members, led by Eoin Morgan, take to the field for the third ODI, they will only think of playing some good cricket and win the series 3-0.
England moved to plug the gaps caused by their mini-injury crisis calling up Steve Finn, Liam Dawson and Toby Roland-Jones to the squad for the final ODI of the series at Lord's.
BEN Stokes cashed in on his remarkable early fortune with a century against South Africa that won England an Ageas Bowl thriller.
Dropped off his first two balls, the 25-year-old then made South Africa pay by plundering 101 from the next 77 he faced.
Two singles were followed by a dot ball, a single and another dot ball.
South Africas sloppy fielding saw ODI debutant left-arm spinner Keshav Mahraj, who bowled much better than figures of one for 72 in 10 overs suggested, have three catches dropped off his bowling alone.
Things were going very smoothly for the visitors until Stokes removed Amla for 24 to give England the crucial breakthrough.
Buttler (65no), who had a close umpire's call for lbw on eight, went on to hit four of five fours in one over off Phehlukwayo as he and Moeen Ali took England's predictable big finish to 111 in the last 10.
Wood defended a target of seven off six balls in the last over.
Part of the reason for that is Ben Stokes.
Jason Roy's indifferent form continued when he was bowled by Rabada for 8 and although Alex Hales and Joe Root assembled a half-century stand at more than a run a ball, two quick wickets further undermined England's prospects.
But South Africa urgently need to revisit the strategy of picking three all-rounder as none of them - Andile Phehlukwayo (1/74), Morris (0/66) and Dwaine Pretorius (0/61) - made an impact with the ball. Stokes' first delivery saw Maharaj draw a thick edge, only for Amla to miss it completely at slip; then de Kock could not hold a more hard opportunity, again off the outside edge of the bat.