Schafer will take charge of the remaining Concacaf qualifying games for the Caribbean side in a 4-month stint
Schafer had only been at the Thai club for a few weeks after his acrimonious split with the Thai FA in June following a lenghty public exchange of words.
The UEFA Cup semi-finalist with Karlsruher explained via his Facebook account that his stay at Muangthong was on the basis on friendship and was to only help steady the team.
"I stayed with Muangthong as a friend, helped them to bring the team back on track," he wrote on his Facebook account.
"That mission was successful, who every (sic) watched the last games saw a team full of confidence, inspired by team spirit and a strong will to success (sic). In the future we can expect a lot of them."
He also thanked his supporters for their kindness and adding: "In spite of all difficulties and all the trouble, I loved my time in Thailand. Because you are all lovely and fair, supportive and simple good friends. You made my time in Thailand a good time."
Schafer takes over from Theodore Whitmore who was asked to step down following a disappointing World Cup qualifying campaign that culminated with a recent defeat to Honduras. He has signed a 4-month contract expiring in November to oversee the Reggae Boyz remaining four Concacaf qualifying matches.
"We still have a small chance to qualify for the World Championship in Brazil and it would be great if you could support us from time to time," was the sign-off from the colourful coach as he wished Thailand all the best.