YAYA TOURE - PEP GUARDIOLA OFTEN HAS PROBLEM WITH AFRICANS

Yaya Toure, the four times African footballer of the year, Ivorian Footballer, ex manchester city player has allegedly said that his two times coach (Barcelona and Manchester city) Pep Guardiola often has problems with Africans, that he was jealous and cruel to him.
After the arrival of Pep Guardihola to the Manchester city club,things changed for Yaya Toure who was the then heart of the Manchester city team where he won six major trophies  but started just one Premier League game in City's latest title-winning campaign - their final home fixture of the season against Brighton was relegated to the bench.
Questions - why would a talented player of Yaya's caliber without injury be relegated to the bench?
Why will the sudden turnaround happen when Pep Guardiola became coach of Man city.
Do you think this is true? If yes..or No..why? We need your thoughts on this.