The 76ers don’t know when Markelle Fultz might be ready to return to action, but Fultz’s agent is optimistic that the second-year guard will play for Philadelphia again this season.Agent Raymond Brothers told ESPN’s Adrian Wojnarowski on Tuesday that Fultz, 20, is seeing improved strength and mobility in his right shoulder.Earlier this month, after visiting a number of doctors, Fultz was diagnosed with thoracic outlet syndrome (TOS), which causes compression or irritation of the nerves or blood vessels in the area between the lower neck and upper chest.”TOS (results) in abnormal functional movement and range of motion, thus severely limiting Markelle’s ability to shoot a basketball,” Brothers told Wojnarowski on Dec. 4.At that point, Fultz already had been sidelined for nearly a month with what was initially viewed to be just a sore right shoulder.Fultz, who played only 14 games in his rookie season due to a right shoulder ailment, has played in 19 games this season, averaging 8.2 points, 3.7 rebounds and 3.1 assists while shooting 41.9 percent. Last season, he averaged 7.1 points, 3.1 rebounds and 3.8 assists, and he shot 40.5 percent.Sixers general manager Elton Brand had said Saturday that the team was waiting to hear more about Fultz’s status and that there was no timeline for the player’s return.Fultz has been rehabilitating away from the team in Los Angeles, but he rejoined the 76ers on Tuesday for their Christmas Day game at Boston. Brothers told Wojnarowski that Fultz would soon return to Los Angeles.Fultz was the No. 1 overall pick in the 2017 NBA Draft out of the University of Washington.