Opening batsman Dean Elgar was defiant with an unbeaten 72 as South Africa slipped to a precarious 117 for four, still 375 runs short of a 492-run target.
Ben Stokes took two wickets in two balls to leave England eyeing victory as the visitors plunged to 52-4. Elgar (72 not out) and Temba Bavuma (16 not out) took them to stumps with an unbroken 65 run stand.
Earlier, England declared at 313-8 after Tom Westley completed a maiden Test fifty. Westley (59) and Root (50) were supported by Jonny Bairstow's a run-a-ball fifty.
South Africa 175 and 117 for 4 (Elgar 72*, Bavuma 16*) need a further 375 runs to beat England 353 and 313 for 8 dec (Bairstow 63, Westley 59, Root 50, Maharaj 3-50).
Matches Tagged in ClipDex2017 ENG v RSA 3rd Test
Series Tagged in ClipDex2017 ENG v RSA Test serie ...
Players Tagged in ClipDexBairstow, Jonathan M Westley, Thomas Broad, Stuart C J Elgar, Dean Roland-Jones, Toby Bavuma, Temba Maharaj, Keshav A Root, Joseph Edward Philander, Vernon D Stokes, Benjamin A Du Plessis, Faf
Grounds Tagged in ClipDexThe Oval
Categories Tagged in ClipDexTest Matches