Bayern Munich’s 72-year-old coach was suffering with illness and fell asleep before Bayern kicked-off against Schalke on Saturday evening, missing two of the game's three goals.
"On Friday and Saturday I felt really bad,” Heynckes told a press conference on Friday before Bayern’s trip to Wolfsburg on Saturday. “And on Saturday I went to bed at 16:45 and you know when I woke up? Just after 19:00... when the Bayern game had already been running for 35 minutes.
“Because of that, I had a very bad conscience,” the coach admitted.
There were question marks as to whether Heynckes would be in the dugout for Bayern's Matchday 23 clash with Wolfsburg after missing the Schalke win with a cold. But the league's oldest coach confirmed that he is now well enough to return.
Heynckes hasn’t had much time to rest since taking over from Carlo Ancelotti as Bayern boss, but when asked if he used the time off to consider any squad options the former Borussia Mönchengladbach striker replied with his typical humour.
“When I lay in bed, I try to sleep,” Heynckes told reporters.
There will be no sleeping this weekend for Bayern's coach, the team, or Spanish midfielder Thiago, either. The 26-year-old is fit again and Heynckes confirmed on Friday that he will start against Wolfsburg, making his first appearance for the club in three months.