Questions had been asked of how the holders would fare at the start of their title defence amidst some behind-the-scenes rows in the South Africa camp over non-payment of player salaries and the decision of star Thembi Kgatlana to miss the tournament for personal reasons.
However, coach Desiree Ellis will no doubt be pleased with a convincing performance against the West Africans.
Motlhalo was cool and calm from the spot, slotting home into the bottom-right corner, and Seoposenwe, who will retire from international football after the tournament, added a clinical first-time finish.
The Black Queens were denied clear-cut chances in the first half, and the closest they came to scoring was when Asantewaa tried an ambitious long-range shot in the 40th minute and forced a save at full stretch from South Africa goalkeeper Andile Dlamini.
Ghana improved after the break, showing more purpose and composure in their play, yet Seoposenwe passed up two openings to increase South Africa’s lead.
First the forward shot straight at Konlan following a breakaway and just after the hour mark a one-on-one went to waste after she was played in by Motlhalo’s weighted pass.
The second of those chances came soon after Kusi’s shot rebounded off a post with Dlamini beaten, and Ghana substitute Princess Marfo then forced an alert save from the South Africa keeper.
The West Africans were denied by the post for a second time in the 77th minute as Comfort Yeboah’s cross was met by Badu.
Next up for Kim Bjorkegren’s side is an outing against Mali on Friday, with South Africa facing Tanzania later the same day.
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