Leg spinner Danish Kaneria struck twice before the close to keep alive Pakistan's hopes of winning the deciding third test against South Africa on Saturday.
South Africa, chasing 161 to win, were 36 for two at the end of the second day, Kaneria taking two for two in 2.1 overs.
Earlier, Pakistan were bowled out for 186 in their second innings. Fast bowler Dale Steyn was the chief destroyer, finishing with three for 47.
The pitch offered pace, bounce, movement off the seam and turn, and challenged all the batsmen.
The hosts, resuming their first innings on 131 for five, lost five wickets for 52 runs in 14 overs.
Wicketkeeper Mark Boucher cracked five fours and two sixes in an unbeaten 40, sharing a useful stand of 43 with Steyn (three) for the ninth wicket.
Kaneria claimed three for 44 while paceman Mohammed Sami picked up three for 53.
Pakistan then lost an early wicket when Steyn prompted Mohammad Hafeez to slash a catch to backward point Ashwell Prince on 10.
CAUGHT BEHIND
Steyn also trapped Imran Farhat lbw for 13 before fast bowler Makhaya Ntini had Younis Khan caught behind by Boucher for a duck.
Andrew Hall then bowled Mohammad Yousuf for 18 off his pads with an inswinger. It was only the 17th time in 126 test innings the Pakistan strokeplayer had been bowled.
Hall followed up by having top-scorer Yasir Hameed smartly caught by Prince at backward point for 35.
Pakistan slumped to 111 for six before tea when Kamran Akmal pushed forward to left-arm spinner Paul Harris and was stumped for six.
Steyn had Inzamam-ul-Haq caught behind for 22 before Shahid Nazir and Sami halted the slide with a stand of 55 for the eighth wicket, only the third half-century partnership of the match.
The stand was ended when Jacques Kallis had Nazir caught behind for 27. In his next over, Kallis had Sami caught on the pull by mid-wicket Hashim Amla for 31.
Kaneria, though, kept everyone guessing about the eventual outcome of the match with two quick wickets in South Africa's second innings.
Boeta Dippenaar, on three, was first to go when he looped an attempted sweep to keeper Akmal.
Kaneria then struck again, trapping nightwatchman Harris lbw for a duck with a flipper.
Captain Graeme Smith batted aggressively, scoring 33 not out in 34 balls and hitting six fours.
Pakistan 1st innings 157
South Africa 1st innings 183
Pakistan 2nd innings:
Mohammad Hafeez c Prince b Steyn 10
Imran Farhat lbw b Steyn 13
Yasir Hameed c Prince b Hall 35
Younis Khan c Boucher b Ntini 0
Mohammad Yousuf b Hall 18
Inzamam-ul-Haq c Boucher b Steyn 22
Kamran Akmal st Boucher b Harris 6
Mohammad Sami c Amla b Kallis 31
Shahid Nazir c Boucher b Kallis 27
Danish Kaneria not out 1
Mohammad Asif c Prince b Harris 6
Extras (b-6 lb-2 nb-4 w-5) 17
Total (all out, 51.2 overs) 186
Fall of wickets: 1-17 2-28 3-44 4-83 5-92 6-111 7-121 8-176.
Bowling: Ntini 10-2-41-1, Steyn 13-3-47-3 (nb-4), Kallis 7-0-36-2 (w-5), Hall 7-1-23-2, Harris 14.2-31-2.
South Africa 2nd innings
G Smith not out 33
B Dippenaar c Kamran Akmal b Danish Kaneria 3
P Harris lbw b Danish Kaneria 0
Total (for 2 wkts, 11.1 overs) 36
Fall of wickets: 1-30, 2-36
To bat: H Amla, J Kallis, A Prince, A de Villiers, M Boucher, A Hall, M Ntini, D Steyn.
Bowling: Mohammad Asif 5-1-19-0, Shahid Nazir 3-0-15-0, Danish Kaneria 2.1-0-2-2, Mohammad Hafeez 1-1-0-0.
