Sinner vs. Khachanov, Tsitsipas vs. Fritz
Getty Images Red hot Jannik Sinner will face his first big test of 2024 against 2023 Australian Open semifinalist Karen Khachanov on Sunday afternoon, while Taylor Fritz battles Stefanos Tsitsipas for a spot in the Australian Open quarters. (4) Jannik Sinner vs. (15) Karen Khachanov Nobody has looked better through the first week of play…