كتب : Omar AbdelAziz
The 24-year-old Rensing was handed the responsibility of holding the No.1 shirt for the Bundesliga giants for the first time, following the retirement of goalkeeping legend Kahn last season.
However, Rensing conceded nine goals in five league games and was recently lambasted after a grim performance in last weekend's 5-2 drubbing by Werder Bremen at Allianz Arena.
But King Kahn defended his former partner as he conceded that his early days in Bavaria were not quite glamorous as well.
"I have always said: if you build your team with youth in mind, you have to accept their may be difficulties along the way and a bumpy road," Kahn told German daily Bild.
"It could have very damaging consequences if Michael is called into question now.
"My first season (1994/95) at Bayern was a disaster up until I tore my cruciate knee ligament.
"Everything I touched there did not turn to gold, quite the opposite for me.
"And at that time, people called for my predecessor Raimond Aumann to return."
Rensing could face competition from Germany international guardian Hans-Jorg Butt, who was signed as a back-up keeper in the summer.