England require 125 runs to claim the victory from the third Test encounter against South Africa at Lord's this afternoon.
However, they have just three wickets remaining as their grip on top spot in the world rankings appears to be loosening.
Jonny Bairstow was the first go in the afternoon session when he was bowled by Imran Tahir for 54 runs.
Jonathan Trott soon followed Bairstow back to the pavilion when he was caught by Jacques Kallis with 63 runs to his name.
That brought Matt Prior and Stuart Broad to the crease and both went about hitting numerous boundaries, frustrating the South African bowling attack in the process.
Broad was eventually dismissed for 37 runs when he was caught in the deep by Hashim Amla. Prior remains unbeaten on 35, alongside Graeme Swann with 12 as England closed for tea on 221-7.
Defeat for the home side will see them lose the three-match series 2-0.
