I had never ever heard of him before! And I had heard of Sijsling so this must have been a big win for Thanasi?
It is, but I wouldn't have been surprised with a victory had he been fully healthy the whole match. The kid has GS winning potential I think, and for me is Australia's most promising young player (close between him and Kyrgios), including Tomic.
However to do it hurting so badly with cramp was very impressive. He practically served underhand in the last set, and just hit flat foot winners the whole time. Sijsling had less serious cramp issues and played like crap the last set but it was still impressive. He looked very very close to retiring at 4-2 in the last set but kept on.