Valdes fell out with Van Gaal at the end of the 2014/15 campaign after the veteran coach thought his back-up goalkeeper had been unwilling to play a reserve team game.
Valdes was later banished from the first-team squad altogether and even denied a place in the dressing room as Van Gaal looked to push him out. Yet despite an unsavoury few months, the ex-Barcelona stopper insists there are no hard feelings.
"I don't have any bad words for Van Gaal or Manchester United. They helped me through my injury and the manager gave me my chance as a footballer at Barcelona and then again at United," the 34-year-old told Sky Sports News.
"He's like a father figure to me. I don't want to remember the last six months in a bad way - for me he is in the top. We are still friends and there is no problem between us," Valdes added.
The three-time Champions League winner was left without a club when his Barça contract ended in 2014. He was nursing a serious knee injury at the time and was invited by Van Gaal, the man responsible for handing the player his senior debut over a decade earlier, to train in Manchester.
That resulted in an 18 month contract, and, if nothing else, it served to resurrect Valdes' career. Now with Boro, he's starting a new chapter and feels like he's turned a corner after the "hard days" spent in Manchester.
"This was the biggest fight of my career and I won it. The easy way out was to end my career but now I feel like a professional goalkeeper again," he said.
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