Jan Siewert said Huddersfield were not at the same level as Chelsea after their 5-0 defeat at Stamford Bridge.
Gonzalo Higuain and Eden Hazard both scored twice as the home side eased to victory to return to the top four.
Huddersfield remain rooted to the foot of the Premier League table, 12 points from safety, and new manager Siewert said: "I don't feel good because we lost 5-0 and we can't compete with Chelsea. We can't compare our clubs at the moment.
"We tried everything to beat them but they showed they are also very hungry because of their defeat against Bournemouth."
Huddersfield did spurn an early chance when Aaron Mooy headed over, but otherwise only occasionally threatened on the break.
"We missed several moments when we could have shot," said Siewert. "It's possible to threaten but you have to shoot. Sometimes the ball goes for a corner or goes to goal, which is the important thing."
Siewert was also unsure about Chelsea's second goal, which came from a penalty after Cesar Azpilicueta was fouled right on the edge of the box.
"It was a very bad moment for us. We had some chances before and then maybe we could have equalised before half-time and I'm not sure if it was a penalty," he said.
"We have to work as intensely as possible and for my game you need the right shape for that. To be intense and defend at the front is the most important thing. We have to work hard and continue.
"It's definitely a test of character. Our fans were fantastic and we have to show that we are willing to win games."