US Open mixed doubles: Draper/Pegula into semi-finals after beating Alcaraz/Raducanu – as it happened

Here is a summary of the news article in 150-200 words: The US Open mixed doubles event has reached the semi-finals stage. Several high-profile players have advanced, including Iga Swiatek/Casper Ruud, Jessica Pegula/Jack Draper, and Danielle Collins/Christian Harrison. The format for the remaining matches has been modified, with the last 16, quarter-finals, and semi-finals being best-of-three sets, but the first to four games, not six. If a game goes to deuce, the next point decides the winner, with no advantage. If the match is level at one set apiece, a 10-point match tiebreak will determine the winner. In a late development, Danielle Collins and Christian Harris have replaced Sinner/Siniakova in the semi-finals. The article provides a concise summary of the key events and format changes in the US Open mixed doubles tournament, focusing on the players who have reached the semi-finals stage and the unique scoring system being used for the later rounds.