Glory suffered their third consecutive defeat but Mitchell said Perth's display against the Reds was significantly better than their loss to Newcastle Jets last week by the same score.

Mitchell said Perth were right in the contest until United opened the scoring in the 70th minute, before Sergio van Dijk doubled the lead minutes later.

The Glory boss conceded the tie was effectively over when Chris Coyne received his marching orders in the 75th minute for a second bookable offence.

"Overall I was quite happy with the performance but not the result," he said.

"I think we played well tonight, there wasn't much between the teams. I think we were starting to control the game when they scored. Then we were looking at making a couple of changes then they got a penalty. Scoring the penalty sort of killed us and then we lost a man and made it very difficult for us.

"The performance was good and the game could have gone either way up until they scored. It was disappointing for our point of view. It was disappointing but the effort the boys put in, we contained Adelaide and they weren't causing us many problems other than when they scored the goal."

Mitchell denied Perth were outplayed and unable to match United's new crisp passing, possession orientated attacking style of play.

He also refuted claims the Glory's own distribution was poor and their passing untidy, although the Reds appeared a much more fluid side.

"Adelaide don't play too many passes they bomb it long behind defences so they put you under a lot of pressure," he said.

"They don't tend to pass it that well either. So, from our point of view you've got to be able to compete against that and that's what we did and it makes it difficult for you to make passes. You're playing away from home, they put you under a lot of pressure and they've got a lot of power and pace in their side."

Mitchell did praise the league leader, labelling the Reds as a well organised and powerful outfit, and admitted he was surprised United finished with the wooden spoon last season.

He said some handy acquisitions have seen them return to the top of the league and remained upbeat despite the loss, hinting the Reds opening goal may have been more than a little fortunate.

"They're well organised, they're quite powerful, they've got a lot of pace," he said.

"I thought they were a great side last year and it was surprising where they came. They've added a couple of players of quality in different areas and they've always had Galekovic, a class keeper, the best keeper in the league and he's made two world class saves early on and kept them in the game.

"It's not doom and gloom, it was certainly a good performance from our boys tonight and it could have gone either way. Adelaide are a very good side.

"The cross came in, I think van Dijk sort of just got down low and it's hit the top of the back of his head and flipped over our keeper. It was a fluke, but it was a goal."