Sir Alex Ferguson had zero doubts when naming the one Man Utd player he 'never got the best out of' and it haunts him to this day

Sir Alex Ferguson was in no doubt when he named the one Manchester United player he failed to get the best out of during his time at the club.

Ferguson, 83, is the most successful manager in Premier League history, having secured 13 top-flight titles during his time at Manchester United.

However, he didn’t always get every decision correct despite his success at Old Trafford.

The Scot signed the likes of Wayne Rooney, Cristiano Ronaldo and Carlo Tevez, who went on to have successful careers at United, but it was another forward who caused Ferguson to reportedly admit that selling him was a “mistake”.

Speaking in the book ‘Bring on United’, Ole Gunnar Solskjaer told a story of a conversation he had with Ferguson about Uruguayan striker Diego Forlan.

Solskjaer said: "He [Forlan] was a very nice guy and when the lads came in from abroad, we'd try to talk to them because I knew what it was like to come in as an outsider.

"He could shoot with both feet, but unfortunately, it didn't work out for him at United. We knew what a good player he was and he'd go on to be the best player in the 2010 World Cup to prove that.

"I remember the chat I had with the gaffer [Sir Alex Ferguson] about players after they'd left and he said: 'Diego Forlan was a great player. It was my mistake that I never managed to get the best out of him'."

Forlan, 45, played for United between 2002-2004 and registered 17 goals and eight assists in 98 appearances for the Red Devils.

Diego Forlan in action for Man Utd (Credit:Getty)

However, he is still fondly remembered by United fans for his brace against Liverpool at Anfield in 2002.

Forlan, who is now a professional tennis player, discussed his time at United during an interview with The Telegraph back in 2014.

“I feel lucky because I was at one of the best clubs in the world,” said Forlan. “I won three titles: the Premier League, the FA Cup and the Community Shield. I remember with special fondness a last minute goal against Chelsea, another against Southampton, a volley I scored against Glasgow Rangers in the Champions League and of course the two goals I scored against Liverpool at Anfield."