John Harbaugh has said that the Baltimore Ravens did not protect the ball well enough during their pre-season loss to the Carolina Panthers.
The NFC South side returned a punt for a touchdown before the defense added three scores to inflict a 34-27 defeat on the Super Bowl champions.
The head coach told the Ravens' website: "We have to protect the ball better. We know we can do that, but we didn't.
"Very pleased about really most everything about the game. I liked the way we played. I liked how we played, I just didn't like the four returns for touchdowns."
Quarterback Joe Flacco added: "It was just a lot of miscommunication. Tonight was one of those games that we did a lot of good things, but we had some miscommunication and turned the ball over too much."
The Ravens will play the St Louis Rams in the final pre-season game next week.