The 67-year-old Heynckes said he would retire in May with Pep Guardiola, the former hugely successful Barcelona coach, taking over from next season in a major coup for the Bavarians announced late on Wednesday.
"We have to have full understanding for [Jupp Heynckes'] decision both as friends of Jupp Heynckes and as a club. We have to accept and respect it," said Bayern CEO Karl-Heinz Rummenigge, after a 70-minute talk with the coach.
"In a very personal discussion we both agreed we must now - especially now - do everything so that Bayern and Jupp Heynckes have a successful second half to the season and bring the league title to Munich."
It is unlikely the spectacular transfer will deter Bayern from their goal to restore order in the Bundesliga after back-to-back titles for Borussia Dortmund.
The Bavarians, nine points clear at the top with Bayer Leverkusen on 33 and champions Dortmund third on 30, have unrivalled firepower, having scored 44 goals for the best offence in the league.
Toothless Fuerth have netted four times less for the worst record in the Bundesliga this season.
Heynckes, who led Bayern to the Champions League final last season but has so far failed to win any silverware in his third spell at the club, will also have a fit squad to choose from apart from long-term injured Holger Badstuber.
Dutch winger Arjen Robben, who missed much of the first half through injuries, has come back fully fit.
"What will be important is that we stay focused and concentrated against a team desperate to stay up," Brazilian defender Dante said.
"It will be an uncomfortable game because they will work hard and wait for the break. We have to be alert so there are no bad surprises in the end."
Second-placed Leverkusen, who finished strong in December with five wins out of six, host fourth-placed Eintracht Frankfurt, also on 30 points, with striker Stefan Kiessling in superb form this season.
Champions League competitors Dortmund, traveling to Werder Bremen, are in equally good spirits since the return of gifted playmaker and crowd favourite Nuri Sahin following unsuccessful spells at Real Madrid and Liverpool.
"We are still involved in every competition and that is the important thing," said keeper Roman Weidenfeller. "We work hard we want to improve and we want success."
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