Joel Embiid was hampered by fatigue in the second half of the Philadelphia 76ers' loss to the Indiana Pacers, according to Brett Brown, who acknowledged the center has "a lot on his shoulders".
A superb first-half display saw Embiid score 28 points off nine-of-15 shooting and grab 14 rebounds, sending the 76ers into the interval with a 10-point cushion at Wells Fargo Center.
The All-Star, who was unhappy about being rested for a game against the Detroit Pistons last week, lost some of his momentum in the second half but still finished the game with 40 points and 21 boards, albeit his efforts were unable to prevent the Pacers rallying for a 113-101 triumph.
Brown felt Indiana's physical defense played a significant role in Embiid's decreased production in the defeat.
"I think their physicality got the better of us. They are the second-ranked defensive team in the NBA and we felt all of that. I thought they were just more physical," said Philadelphia's head coach.
"I think that Joel's world changed in the second half. Joel was dominant in the first half, it was difficult getting him the ball and when we did we had some turnovers trying to get him the ball. They did a good job of fronting the post, playing in front of him.
"I think he's got a lot on his shoulders as far as the weight of our expectations on him. He certainly expended a lot of energy in the first half, but I felt like he fatigued and I give some of that credit to Indiana because of how physical they were."
However, Embiid did not believe he struggled to cope in a more physical battle and was unsure why he failed to remain the game's dominant force.
He said: "They adjusted so I'm not sure [why things changed], I've got to go back and watch why the same thing didn't happen in the second half. I tried to be aggressive, keep the same intensity, but that's a lesson to learn.
"It wasn't [more physical], it was the same thing and I'm going to learn from it."