Sancho, who joined United from Borussia Dortmund in July 2021, returned to training in January for the first time since October and has struggled for form.
However, on Thursday, he had some bright moments when United secured Champions League qualification with a 4-1 win over Chelsea.
Sancho started on the left flank, but following an injury to fellow forward Antony, he switched to the right and assisted Anthony Martial's goal to put United 2-0 up.
"He did very well on the right side, and I think he played a very good game," Ten Hag said ahead of Sunday's home game against Fulham. "There was an injury, so I took the chance to give him some instructions... He did very well on the right.
"Sancho was one of the players who (has made good) progress in this season... It's a good base to build further on. He can do both (wings) but I think he prefers to play on the left."
Ten Hag said he was unsure if defender Luke Shaw, who was forced off against Chelsea with a back problem, would be available to face Fulham.
The Dutchman said the extent of Antony's foot injury was not yet known after he had to be carried off the pitch on a stretcher.
Three-time European champions United, who failed to qualify for the Champions League last season, will face rivals Manchester City in the FA Cup final on June 3.
