South Africa are themselves missing regular captain Faf du Plessis, who has opted out of the first match of the four-test series due to family reasons, leading batsman AB de Villiers and pace spearhead Dale Steyn.
Thursday's match will be Joe Root's coronation as England's new test captain, while the hosts are missing injured pace duo Chris Woakes and Jake Ball.
England's experienced pace duo James Anderson and Stuart Broad are also returning to the side after injury-forced absences.
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"New leadership, a few new faces in their batting line-up, a few injury concerns," Elgar told reporters.
"Sitting here as a South African player I see it as a good opportunity for us to try and make a dent.
"They have their own insecurities within their team. They're under new leadership and everyone is asking Root what his captaincy is going to be like."
The Proteas, ranked number two in tests, have won their last two series in England and also won in Australia in their last visit Down Under.
In the absence of Steyn, Elgar is banking on the 22-year-old pace sensation Kagiso Rabada to lead the South African attack in seamer-friendly English conditions.
"I'm glad he (Rabada) is in my team. He's been a find and he's taken to international cricket brilliantly," Elgar added.
"Those were the characteristics we expected he would show at this level. I'm sure he'll be up for it. He hasn't played a lot of cricket of late so I'm sure his hunger is through the roof.
"You can see the way he's bowling in the nets. He's fresh and willing to go. If he hits his straps he's going to be something exciting to watch."
(Writing by Sudipto Ganguly in Mumbai; Editing by John O'Brien)
