Thomas Müller has been a regular for Bayern Munich for more than a decade. He has made 451 appearances for the Bavarian club and is still only 29-years-old.

It was therefore somewhat surprising that Niko Kovac left Müller on the bench for the entirety of Bayern's 3-1 win over Wolfsburg on Saturday. That had happened only 17 times before in Müller's 10-year career, and six of those instances came when he was a teenager.

That is how much Müller's form has dropped off. After a goal and an assist in his first two league games, he has zero goal contributions in Bayern's last seven matches. James Rodriguez and Serge Gnabry have provided a spark in the meantime, and both started over Müller over the weekend.

But Bayern's Champions League matchup against Greek side AEK Athens on Tuesday is a great opportunity for Müller to rediscover his goalscoring quality. After getting the weekend off, there's a good chance Müller gets the start in the Champions League, and Bayern need him to return to form.

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Still essential to Bayern's success

Throughout Müller's career, Bayern have won 92 percent of the games in which he registered a goal or an assist and only 59 percent of the games in which he didn't.

It therefore hasn't helped that his production has dropped off in recent seasons. Müller's down season in 2016-17 in which he scored just nine goals coincided with Bayern's underwhelming quarterfinal exit from the Champions League and disappointing semifinal exit from the German Cup. It wasn't until Jupp Heynckes returned last season that Müller showed signs of the goalscorer he once was.

His dry form this term is one of the reasons for Bayern's woes — they are still in fourth place in the Bundesliga table and drew with Ajax in the Champions League earlier this month. It wasn't until Saturday's match against Wolfsburg that Kovac was finally brave enough to leave the former World Cup champion on the bench.

When he gets the chance, however, Müller has been a menace against Champions League teams drawn in Bayern's group from pot four, which AEK Athens were earlier this season. He has scored six goals and recorded three assists in 16 games (10 starts) against pot four teams.

Perhaps a rebound performance in Greece, who are missing two of their better defenders in Marios Oikonomou and Hélder Lopes, may be what Müller needs to get back to his goalscoring self.

Crucial Hoffenheim test against Lyon

It was clear last season that Hoffenheim were not ready to make strides in the Champions League after losing to Liverpool 6-3 on aggregate in qualifying.

Though they put in a good performance in their draw with Shakhtar Donetzk and their defeat at the hands of Manchester City, Hoffenheim are still without their first-ever Champions League win. However, they can make a statement by beating Olympique Lyon in Sinsheim on Tuesday.

The French side, after all, spent 10 straight seasons in the Champions League between 2002 and 2012. They have also churned out some of the best young French talent, some of whom featured in France's World Cup win in Russia.

Collecting their first win would be a huge step forward for the Rhein-Neckar club as they try to establish themselves as a legitimate European side.