Carlos Alcaraz looked little like the player who won two Grand Slams this year in a 6-1, 7-5 loss to Casper Ruud at the ATP Finals

Norway's Casper Ruud eased to a straight-sets victory over Carlos Alcaraz on Monday as the Spanish star's bid for a maiden ATP Finals title got off to a poor start.

Carlos Alcaraz struggled with a stomach issue and looked far from the player who won two Grand Slams this year in losing to Casper Ruud 6-1, 7-5 at the ATP Finals on Monday. It marked Ruud’s first victory over Alcaraz in five career meetings,

The ATP Finals is only two days in, but there have already been some significant results. Ahead of round two of group stage action, we look at how the rankings shake up after Sunday and Monday’s results.