Rodgers admits his Liverpool side remain a work in progress but still saw some encouraging signs in the opening 45 minutes.
He said: "We showed some signs of our quality but the penalties and the sending-off kills you, especially a new team coming together.
"But I've got to give big credit to the players. They ran to a standstill today and I can't complain.
"It is still a work in progress. It is very much a marathon we are in. This is the first game.
"We've got to win games. I've heard lots about patience and every manager wants that. But nowadays you don't get that. We've got to win games. It was a bad day in the office."