Cape Town, January 4: Sam Curran said England must dismiss South Africa early on day three and "bat big" after Ben Stokes' catches and a fired-up pace attack gave them the edge in the second Test at Newlands.
Curran and Stuart Broad took two wickets apiece on Saturday, while James Anderson claimed 3-34 to leave the Proteas 215-8 at stumps in reply to the tourists' 269 all out, having been 157-3 shortly after tea.
Stokes took four slip catches and put down two other chances, leaving him one away from becoming the first England fielder, excluding wicketkeepers, to grab five in a Test innings.
South Africa trail by 54 runs and Curran says England must take command on Sunday (January 5) as they strive to level the four-match series at 1-1.
"What a way to finish the day. Hopefully we can get a lead," Curran told Sky Sports.
"We're in a good position. Hopefully we can get those two wickets in the morning and bat big."
Dean Elgar (88) and Rassie van der Dussen (68) were looking like giving the hosts a platform to build a big lead, the latter capitalising on being given a reprieve when he edged behind on 16, but Broad overstepped.
Spinner Dom Bess bowled 27 overs, foraging for an opening before he claimed the crucial fourth-wicket breakthrough, drawing Elgar into a hoik that found the safe hands of Joe Root.
"Bessy did an amazing job. There's not much for the seamers and not much for Bessy," Curran said.
"That is a flat wicket but at the same time there is a channel that we're trying to hit. It's about being as patient as possible and every now and again there's something there."