Leroy Sané celebrates after scoring Bayern's second against Barcelona.
CNN  — 

For eight seasons, Bayern Munich fans had become accustomed to watching Robert Lewandowski find the back of the net on almost a weekly basis.

The Polish striker, one of the greatest forwards in the club’s history, returned to the Allianz Arena on Tuesday for the first time since swapping Bavaria for Barcelona in the summer – and it wasn’t quite the return he would have hoped for.

Lewandowski missed a number of golden opportunities – one in particular in the first half, eight yards from goal, that he would usually score in his sleep – to leave the door open for Bayern to grab a crucial 2-0 win in this Champions League heavyweight clash.

Second half goals from Lucas Hernandez and Leroy Sané secured the three points and extended Bayern’s remarkable unbeaten run in the Champions League group stages to 30 matches, a streak that stretches back to 2017.

Once Barça’s “economic levers” had been activated to allow the club to register its summer signings, Lewandowski hit the ground running in his new home and bagged nine goals in six games prior to Tuesday’s match.

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Robert Lewandowski had a bad night in front of goal.

The 34-year-old received a relatively warm reception from the Allianz faithful on his return, but Bayern fans would have been as delighted as they were surprised to see their former hero miss so many chances.

Profligacy in front of goal aside, there will be plenty of positives for Barcelona and its head coach Xavi to take away from the match, with the team competing for most of the 90 minutes against a Bayern side many predict to go far in this season’s Champions League.

“This result doesn’t tell the true story,” Barça midfielder Pedri said after the game. “Our first half display merited much more than 0-0 at halftime, but of course, if you fail to put chances away against a big rival like Bayern, you’ll end up paying.”

Xavi said he was “pissed off” with the result on a night he felt his team could have won.

“But I’m also feeling proud of the team,” he added. “However, it’s about winning and we’ll need to compete better in crucial moments like the two goals and to be more effective when we create chances.”

Lucas Hernandez celebrates after scoring Bayern's opening goal.

However, it hasn’t exactly been plain sailing for Julian Nagelsmann and Bayern in recent matches.

Eyebrows are raised any time the team fails to win a match in the Bundesliga and, given the current run of three consecutive draws, perhaps this is as close to a crisis as Bayern can get in domestic football.

The win will certainly help ease any early season pressure Nagelsmann may have been feeling, but the performance of his team for long stretches of the match will still leave a lot to be desired.

Sadio Mané, Bayern’s marquee summer signing from Liverpool, struggled to make much of an impact up against Barcelona’s makeshift right back Jules Koundé, while an angry Sané took his frustration at being substituted out on a bottle in the dugout.

“In the first half, Barcelona had the better chances than us,” Nagelsmann said. “Our final ball wasn’t quite there. It was much better in the second half and our efficiency made the difference.”