Arsenal legend Freddie Ljungberg reveals the ONE weakness he thinks Arsene Wenger's Invincibles had and the 2004 team-mate he admired the most as he admits Champions League regret

Arsenal legend Freddie Ljungberg has opened up on the one weakness he feels the Invincibles had under Arsene Wenger.

The Gunners created history in the 2003-04 season when they went a full league campaign unbeaten, a feat that has not been matched before or since in the Premier League era. 

Ljungberg played a key role in that side, but admits they weren't unstoppable, and has pointed out a weakness that was exposed by Chelsea when Jose Mourinho took over the Blues in 2004.

'One main weakness was if I sometimes came out here, wide right, and people said "Oh, cross the ball, Freddie, you're free just cross it",' Ljungberg explained on Monday Night Football. 'I think it was Mourinho and Chelsea that started to do it, they didn't come out and press.

'So I could stand out here with the ball and the full back didn't come. They'd just stand with their four in the box and they were great headers, John Terry, Carvalho in the middle, and our strikers were not the best in the air.

'So they were just "no, come on, cross the ball". And that, in my opinion, we couldn't really find a threat.'

Ljungberg alluded to how teams appeared to figure Arsenal out after a while, but they still had great success during this period, winning three league titles in six years, with their Invincibles capping off a golden era.

Ljungberg puts this down to having a starting XI where every player could claim to be one of the best three in the world in their position. He refused to name who the best player was, but gave special mention to Dennis Bergkamp, admitting he had great admiration for the Dutchman always putting the team before himself.

'I feel wrong to say Thierry is the best player I played with because I was in awe of all my team-mates. But in terms of technical ability, if you put that out there, I would say someone like Dennis Bergkamp, he did things I’d never really seen,' Ljungberg said.

'He just did to perfection what was needed. It was all so effective. You see him in training, he could do 15 stepovers, but he didn’t because everything was effective for the team. 

'I think that’s why a lot of us players we mention Dennis so often. The respect of him that he could have done so much more for his own ego but he played for the team. And, by the way, Thierry was absolutely amazing!'

Ljungberg was part of two title-winning teams and lifted the FA Cup three times, but the Champions League eluded him.

Wenger's men made it to the final in 2006, but lost 2-1 to Barcelona after goalkeeper Jens Lehmann was sent off early on. Ljungberg stated he is still angry about missing out on Europe's biggest prize.

'It’s my biggest regret in my life. I really hate that I haven’t won the Champions League and I’m still angry about it to this day,' he added. 

'I can’t explain why because we had a great team. The only thing is when we went to a Champions League final and we lost we had changed the system and we went to 4-3-3 and we protected the centre a bit more when we did that. And then we got the sending off of Jens after 20 minutes. That’s the only change for the final. 

'But I can tell you it still eats at me today, I feel very disappointed. But it’s our responsibility, it’s us players. We didn’t do good enough. But when you looked at it you felt like we should win this.'