Though a league match, it has become a virtual quarterfinal with the winner making it to the last four.
The Proteas arrived here from Ahmedabad riding on a morale-boosting 78-run win over Sri Lanka, while Pakistan are in a state of shock at their 51-run defeat to dark horses New Zealand here last night.
Though both the teams have lost to New Zealand and their wins have come against Sri Lanka, it remains to be seen how the Pakistanis recover from last night's setback and whether they have the mental strength to withstand yet another blow after the loss of their regular captain and two key bowlers.
Clearly, their task is cut out for them, for the South Africans, having tasted blood, will not let go the opportunity easily.
The biggest single factor in the crucial tie will be how the respective pace attacks go and here South Africa hold a clear edge.
Against the Lankans on a low and slow Motera pitch, Shaun Pollock, Makhaya Ntini and Andre Nel mopped up seven of the 10 wickets to fall and Jacques Kallis chipped in with the eighth.
And on the sort of track served up here at Mohali, Smith's pace attack is potentially even more lethal. Shane Bond showed just how to get the best out of the conditions here, his second spell in particular being extremely illustrative.
Keeping the ball just short of a length and banging it in, he denied well-set batsmen of the calibre of Mohammad Yousuf and Shoaib Malik the opportunity to go after him. The oft-injured Kiwi pacemen picked up the former and frustrated the latter sufficiently for the disoriented Daniel Vettori to get on to the wicket-takers' list.
Adding to Pakistan's problems is the repeated failures of a key batsman like Shahid Afridi, who now has scores of one (8 balls) against Sri Lanka and four (6 balls) against the Kiwis. Also, he is batting well down the order now and unable to play his natural game, looks a shadow of his aggressive self and that cannot be good news for his captain. Talk here is that he may even sit out the game, such are his levels of confidence now.
And among the seamers, only Umar Gul impressed against the Kiwis and for his side to really test a potentially long South African, others have to step up as well. Rana Naved has been patchy and Abdul Razzaq expensive -- though with some success -- so far. He had 4/50 against Sri Lanka at Jaipur from 7.2 overs and 2/60 here yesterday from 10 overs. These aren't encouraging figures and the Proteas will look to cash in on this is bread and butter stuff for them.
Interestingly, it will also be a clash of a team against their former coach. Bob Woolmer, who was at the helm of the Proteas for two World Cups and put in place a lot of what they still follow, is now on the other side and Smith is looking forward to the meeting.
''He knows about a few of our players. Bob is a clever coach, and it should be interesting,'' Smith said.
Man for man, the South Africans look the better side and the one better suited to the conditions here. Theirs is a long and experienced batting line-up even if it has not really fired yet but Mohali will provide the sort of conditions closest to what they are used to at home and Pakistan will be hard-pressed to hold them back.
But then again, the team from across the Wagah are at their most dangerous when facing seemingly impossible odds and to take them lightly is not something Smith and Co. will do in a hurry.
Pakistan: Younis Khan (Capt) Mohd Hafeez, Imran Farhat, Mohd Yousuf, Shahid Afridi, Shoaib Malik, Kamran Akmal, Abdul Razzaq, Rana Naved-Ul-Hassan, Rao Iftikhar, Umar Gul, Faisal Iqbal, Yasir Arafat and Abdul Rehman
South Africa: Graeme Smith (Capt), Boeta Dippenaar, Herschelle Gibbs, A B de Villiers, Jacques Kallis, Justin Kemp, Mark Boucher, Shaun Pollock, Robin Peterson, Andrew Hall, Makhaya Ntini, Loots Bosman, Charles Langeveldt and Andre Nel.
Umpires: Billy Bowden (NZ) and Mark Benson(Eng) Third umpire: Steve Bucknor( WI) Fourth umpire: Rudi Koertzen (RSA)
Match Referee: Ranjan Madugalle (SL)