Fraizer Campbell has admitted that Cardiff City must quickly understand that mistakes will be punished in the Premier League following their opening day loss to West Ham United.

Goals from Joe Cole and Kevin Nolan condemned last season's Championship winners to a defeat and Campbell believes that Cardiff have some tough lessons to learn.

"Unfortunately we didn't get the result we set out to get. But it's one game into the season and we will go back to the drawing board, watch the game over and look to the next one," the forward told Sky Sports News.

"I think we need to learn quickly that it's an unforgiving league. We could have got away with one or two mistakes last season, but this season you will pay for them. We have to learn quickly, but hopefully we can turn that around.

"There are some positives, it's not all bad. We just have to cut out the silly mistakes. Some bad defending from us has led to two goals. We have to stay strong as a team and work hard during the week."

Malky Mackay's next task is to welcome Manchester City to the Welsh capital on August 25.