Opener Dom Sibley struck a patient maiden century and Ben Stokes produced fireworks at the other end as England raced to 375 for seven at lunch on the fourth day of the second test against South Africa on Monday.
The tourists lead by 421 runs with three-second innings wickets remaining at Newlands to drive home their advantage in a test that increasingly looks as though it can only have one winner.
The highest run chase in Test history was in 2003 when West Indies scored 418 for seven to beat Australia in St John's.
Sibley will resume on 125 not out from 299 balls after playing anchor around which others have been able to play with freedom and is at the crease with Sam Curran (13 not out).
Sibley's previous highest test score going into his fourth match was 29, but he has proven his ability to bat long, one of the key characteristics that drew the English selectors to his talent.
His hundred was met by an almighty roar from the sizeable travelling English support, even if it took him 269 balls to get there.
Stokes was providing plenty of entertainment at the other end as he took on the task of providing the quick runs England want to build a big enough lead and still have enough time to bowl South Africa out a second time.
He smashed seven fours and three sixes in a 47-ball innings of 72, before being caught at mid-on by Rassie van der Dussen off-spinner Keshav Maharaj.
Newlands remains a happy hunting ground for Stokes, though, after he scored his career-best 258 at the ground in 2016.
His blitz propelled England to 157 runs in 27 overs in the morning session and crucially has sped up the game in their pursuit of victory.
The weight of runs suggests the pitch has flattened further after both teams expressed surprise on Sunday as to how the assistance offered to the seamers on the opening two days had disappeared.
South Africa won the first test of the four-match series by 107 runs in Pretoria.