Upstart vs Upstart: Pablo Carreno Busta (L) and Diego Schwartzman have upset the odds to reach so far, but who will make the last four? (Photos: AFP)
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Ace Alert: Kevin Anderson (L) has home favourite Sam Querrey in his path (Photos: AFP)
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Grudge Match: Roger Federer (L) will be out for revenge against Juan Martin del Potro (Photos: AFP)
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David vs Goliath: Top seed Rafael Nadal (L) will seek to avoid an upset against Andrey Rublev of Russia (Photos: AFP)
