PSG visited Bayern's Allianz Arena on Tuesday and a section of the home support unveiled a banner with a profanity aimed at the "plutocratic Al-Khelaifi".
"We concede a lot of goals because we are not stable," complained Guardiola.
Bayern Munich striker Harry Kane hit back at criticism levelled at him, saying he would do his "talking on the pitch" after becoming the fastest to 50 goals in Bundesliga history on Friday.
The German giants, who went without a trophy last year for the first time since 2012, are primed for a return to the winner's circle.
Struggling in Europe after back-to-back losses left them outside the knockout places, Musiala broke through the stubborn Benfica defence, heading in a Harry Kane assist.
Bayern Munich will learn from their 4-1 Champions League defeat to Barcelona but the German team's belief in a successful season is intact, coach Vincent Kompany said on Saturday ahead of Sunday's league game against VfL Bochum.
Bayern Munich coach Vincent Kompany and his Bayer Leverkusen counterpart Xabi Alonso on Friday joined the growing chorus calling for action on player workload, amid talks of strikes.
A street next to Bayern Munich's Allianz Arena stadium will be renamed to honour German football great Franz Beckenbauer who died earlier this year, the city council announced Thursday.
"Something big is coming," Neuer told reporters ahead of Tuesday's opening clash with Dinamo Zagreb at home.
Bayern Munich coach Julian Nagelsmann said he is "not much of a comforter", telling the press on Sunday he decided not to focus on Germany's "bad, sad World Cup" with his side.
Bayern Munich full-back Noussair Mazraoui looks set to miss several weeks after a medical check revealed the Morocco international was suffering from a heart issue.
Bayern Munich CEO Oliver Kahn has acknowledged the challenges of finding a replacement for injured captain and goalkeeper Manuel Neuer in the winter transfer window.
Bayern Munich have signed Netherlands midfielder Daley Blind, the club announced on Thursday evening.
Liverpool will have the chance to avenge last season's Champions League final defeat at the hands of Real Madrid after they were drawn on Monday to face the holders again in the last 16.
Alphonso Davies' unlikely path to spearheading Canada's first World Cup campaign in nearly four decades began in a West African refugee camp where children's dreams are eclipsed by the need to survive.
Bayern Munich right-back Lucas Hernandez returned to training on Monday after a lengthy injury lay-off in a boost to France ahead of next month's World Cup.
Anthony Modeste scored four minutes into added time as Dortmund fought back to snatch a 2-2 home draw with Bayern Munich on Saturday.
Champions Bayern Munich suffered a shock 1-0 loss to hosts Augsburg in the Bundesliga on Saturday to stretch their winless run to four consecutive league matches and drop to fourth place.
Sadio Mane is still adapting to Bayern Munich's style of play but has to be a bit more self-confident, head coach Julian Nagelsmann said after the forward failed to register a shot in their 2-0 Champions League win over Barcelona.