Summarize this content to 2000 words in 6 paragraphs Watch as John Higgins reveals he was struggling with stomach issues during his 5-4 win over Zhou Yuelong in the last 16 of the World Open. The Scotsman ralled from 4-2 down to advance to the 146th ranking-event quarter-final of his career. Enjoy all the action from the World Open live on discovery+.
