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 on Monday. It marked Ruud’s first victory over Alcaraz in five career meetings and the result could make it difficult for Alcaraz to advance from the round-robin stage at the season-ending event for the year’s top eight players. Alcaraz won the French Open and Wimbledon this year to boost his career total to four Grand Slam titles.