The outspoken Bulgarian, 49, revealed that Van Gaal insulted him in front of his wife when they worked together at Barcelona in the late 1990s.
Stoichkov made just four La Liga appearances for Barcelona during the 1997-98 campaign and was subsequently offloaded to CSKA Sofia at the end of the season - and the 1994 Ballon d'Or winner pins the blame squarely on the divisive Dutch coach for his Camp Nou exit.
"I have no respect for [Van Gaal] - he's scum," Stoichkov was quoted as saying by the Manchester Evening News. "One day, when I was injured, I was with my wife at Camp Nou and Van Gaal went up to her.
"He asked her how it was possible that she married someone like me. She responded that I was a Ballon d'Or winner.
"My departure in 1998 was the fault of Van Gaal, for sure."
Van Gaal divides opinion
While many current and former players have plenty of good to say about Van Gaal - such as Victor Valdes and Carles Puyol - others have a totally different opinion, including the likes of Stoichkov, Luca Toni and Franck Ribery.
Other big personalities in the football world also fail to see eye-to-eye with Van Gaal, such as Southampton manager Ronald Koeman and all-time great Johan Cruyff.
Ten months into his Manchester United tenure and there have been a couple of reported incidents involving fall-outs with his current group of players, including Angel di Maria, who is understood to have been involved in a bust-up with Van Gaal after the 2-1 victory over Liverpool at Anfield earlier this month.
Van Gaal is a demanding coach
Van Gaal is a demanding coach who will not take egos into consideration when making big decisions, as United fans have witnessed this season.
Few managers in world football would be brave enough to drop the likes of Radamel Falcao and Di Maria, but Van Gaal will always do what he feels his best for the team, irrespective of whether it upsets players or supporters.
Van Gaal won two La Liga titles and the Copa del Rey with Barcelona before leaving the Camp Nou to take charge of the Netherlands national team in 2000.
Sacked by Barcelona
He rejoined the Catalan giants in July 2002, but was sacked six months later following a run of poor results.
"After reflecting on the recent performances of the club and speaking with Barcelona president Joan Gaspart we have decided that it is in the best interests of the club that we go our separate ways," Van Gaal said at the time. "I am really upset that as a coach I haven't lived up to the expectations of the Barcelona fans."
United expected to stick by Van Gaal
Several weeks ago there were murmurs that Van Gaal could suffer a similar fate with Manchester United, who struggled in the first half of the season but have produced some excellent performances in recent weeks.
Currently on course to qualify for the Champions League following a one-season absence, there is now little doubt that Van Gaal will still be in the Old Trafford hot-seat come August.
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