Johann Berg Gudmundsson could not pinpoint the main reason for Charlton’s relegation this season – admitting many factors had gone wrong.

The Addicks enjoyed a strong start to the campaign, claiming eight points from their first four games against QPR, Derby, Nottingham Forest and Hull.

However, the club’s form soon tailed off and relegation to League One was confirmed last month with three games of the season remaining.

Gudmundsson says mistakes on and off the pitch led to the Championship demise.

The 25-year-old said: “It’s obviously been a disappointment. Last year we did alright but we couldn’t build on that this season which I think is really sad.

“Too many mistakes on the field and off the field – it’s just not been good enough.

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“It’s too many things, having three managers obviously doesn’t help. There’s been too many changes.

“It’s been tough but it’s not just one thing. It’s many factors that have gone wrong – you can’t really pinpoint one thing.”

Reoccurring injuries blighted Charlton’s season with key first-team players such as Igor Vetokele, Ahmed Kashi and Johnnie Jackson missing large spells of the campaign.

Gudmundsson admits the club’s thin squad made these injuries tough to recover from.

“This is a squad that hasn’t been together all season,” he said.

“We started off with a thin squad then we got injuries to key players which obviously didn’t help.

“We brought in players in January so this is not the squad that we’ve had the whole season.”

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Gudmundsson will hope to feature for Iceland this summer at the Euros and could go into the tournament as the Championship’s leading assist maker.

He is currently level with Brentford’s Alan Judge on 11 assists, with Derby forward Chris Martin back on 10.

Despite leading the assist pack, Gudmundsson admits he has endured an “up and down season”.

“Some parts, some parts not,” he said when asked whether he is happy with his personal form.

“Just like as a team we’ve played some good games then not played well.

“It’s been an up and down season. I think I’m top assist in the league so I’ve done something right I think, but it’s difficult to look at that when you’re relegated.”

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