Cardiff - South Africa face a tough task to put their Champions Trophy campaign back on track after being laid low by injuries and a demoralising defeat to India.
The Proteas hopes of winning the tournament slipped when they crashed by 26 runs against Mahendra Singh Dhoni's world champions in a high-scoring opener in Cardiff on Thursday.
AB de Villiers men must now defeat Pakistan in Birmingham on Monday to keep their hopes alive of taking one of the two semi-final spots from group B, which also features the West Indies.
Victory will depend largely on how quickly their two strike fast bowlers, the fearsome Dale Steyn and Morne Morkel, recover from injuries.
Steyn did not play against India due to a side strain suffered during a warm-up match against Pakistan earlier this week, while Morkel limped of with a leg injury while bowling his seventh over on Thursday.
Neither of the key bowlers is a certain starter against Pakistan, who already enjoy a psychological edge following their six-wicket win over the Proteas in the warm-up game.
South African manager Mohammed Moosajee said Morkel had sustained a left quadricep muscle strain and will undergo an MRI scan to determine how serious the injury was.
"It appears to be a grade one strain and he will be going for an MRI scan which will give us a better understanding of the diagnosis and a prognosis," Moosajee said.
"These strains can be tricky in fast bowlers and the healing time in most cases is five to seven days, but if you come back too soon it can cause further disruption and set you back by 10-14 days."
India took advantage of their absence to rattle up 331-7 after being sent in to bat, with left-hander Shikhar Dhawan smashing 114 off 94 balls after an opening stand of 127 with Rohit Sharma (65).
India slipped from 210-1 to 260-5, but an unbeaten 47 from 29 balls by Ravindra Jadeja steered the World Cup champions past the 300-run mark.
The South Africans made a brave chase of the daunting target and replied with 305 following a defiant century stand between skipper AB de Villiers and pinch-hitter Robin Peterson for the third wicket.
De Villiers hit 70 off 71 balls, his sixth half-century in the last eight one-dayers and the fourth in succession. Peterson made a career-best 68.
Ryan McLaren gave India a fright towards the end with an unbeaten 71 off 61 balls, adding 48 for the last wicket with the hobbling Morkel, but the effort was not enough to snatch a dramatic win.
De Villiers said his team made crucial errors, including the run-outs of Peterson and David Miller, but hoped his team will bounce back despite the depleted attack.
"We now have a very important game against Pakistan," he said. "We are going there to win and we have to keep the aggressive mind-set that we had in Cardiff.
"It is basically a do or die. We'd like to win at least two out of the three games. When you win just one out of three, net run-rate come into play. We would not like to have that.
"Each game we play here we have to try to win it. It's a short tournament. There is no room for errors. We'll try to repair that in the next game and go for a big one."
De Villiers hoped Steyn and Morkel will recover fast.
"It will be a big loss not to have them, but I am pretty sure our medical staff and management team will get both of them on the field, hopefully in the next game or, if not, hopefully the last group game."