Giggs ended a 24-year playing career at Manchester United to take up the assistant manager role alongside van Gaal in the dugout.
The much maligned Dutchman guided United to fourth and fifth placed finishes in the Premier League from 2014-16 and also delivered the FA Cup back in May.
However van Gaal was deemed surplus to requirements at the end of the season and United have since hired Jose Mourinho to take over the reins.
‘When I first met Louis we got talking and he asked me to be his assistant after just 30 minutes of conversation.
“I accepted and then he told me that he had one condition. I had to retire. In fact, he said he had made the decision for me,’ Giggs wrote in his column for the Telegraph.
‘I was officially retired as a player as of that moment. As soon as he said so, it felt right.’
The former Welsh winger is adamant that he developed his own coaching prowess under van Gaal and that his former colleague was not solely to blame for the club’s apparent demise.
‘I learned more about coaching from Louis over the next two years than I thought possible. He was completely thorough. Everyone in the team knew their role exactly and in the first season we made good progress. It was only last season that we lost our way although it would be wrong to say that was all Louis’ fault. We must all take our share of the blame.’
Back to May 2013 and Manchester United had won the Premier League title under the departing legendary manager Sir Alex Ferguson.
The following season marked a drastic change of fortunes as David Moyes’ men slumped to a seventh placed finish.
Giggs, who ended the 2013-14 campaign with a brief stint in charge as interm-boss, maintains that Moyes was hindered by poor recruitment. The 42-year-old also suggests that the marquee signing of Marouane Fellaini at the start of Moyes’ season exemplified the ‘panic’ in responding to Sir Alex’s departure.
‘I don’t believe that the decline, post-Sir Alex was inevitable. We won the Premier League by 11 points (2013). There were so many winners in that team, so many great characters.
“Yes, the likes of myself, Rio (Ferdinand), Nemanja Vidic, even Patrice Evra were coming to the end of our careers – although Patrice is still playing,’ continued Giggs.
‘But with the right recruitment we would have been gently phased out and replaced by young, hungry players with United’s winning mentality.’