Former Bayern Munich boss Ottmar Hitzfeld is expecting another difficult season for Thomas Muller at the club.
Muller captained the Bundesliga champions for the opening-day win over Bayer Leverkusen but was relegated to the substitutes' bench for the victory over Werder Bremen a week later.
The Germany international was restored to the starting line-up for the shock defeat to Hoffenheim before again being dropped for the win over Anderlecht in Tuesday's Champions League group-stage opener.
Muller's long-term future at the club has become clouded in doubt since Carlo Ancelotti's appointment as head coach last year, with the forward seemingly unsuited to the Italian's preferred 4-3-3 system.
He was left out of the first XI for key games towards the end of last season, including the DFB-Pokal semi-final loss to Borussia Dortmund, the second leg of the Champions League quarter-final with Real Madrid and the thrilling 5-4 Bundesliga win over RB Leipzig.
And Hitzfeld, who won five league titles and the Champions League during two spells as Bayern boss, believes Muller is clearly not an essential player in Ancelotti's eyes.
"It will be difficult for Muller when the season gets going," he told Focus.
"Ancelotti has sent a signal. When the big games come, you know who's going to be playing."
Rumours of an unsettled dressing-room at the Allianz Arena have increased in the past week, with Bayern's recent performances and the uncertainty around Ancelotti's future drawing criticism from former players including Mario Basler and Stefan Effenberg.
Ancelotti has been tipped to move to the Chinese Super League as soon as January, although the former Madrid boss has denied any such agreement has been reached.
Bayern continue their title defence against Mainz on Saturday.