Despite this, Lewandowski did not appear to be the best rated player of the game but he was the worst rated player based on the aiscore. Kounde and De Jong were the two players who had the highest ratings in that match, but I agree that overall Barcelona didn't perform as good as expected in that match.
Lewandowksi isn't good like his was, I think his performance is declining in this season. If Joao Felix can show a good performance, I believe Barcelona will sign him to replace Lewandowski's position.
There have been many factors who affected his performance. Lewandowski needs another good attacker to help. It doesn't mean barcelona bought felix to be a replacement for lewandowski or backup for him. Barcelona is willing try to pair him with lewandowski.
Look at what he has said in last interview.
https://www.goal.com/en-kw/news/robert-lewandowski-aims-apparent-dig-barcelona-boss-xavi-slow-start-to-season/blt338abe8048eb92e8Osasuna is really good in counter attack, they can maximize their chance to score a goal. While Barcelona only keep passing in order to make them looks more dominant and giving pressure to Osasuna.
This club is also good in defense as well. Osassuna's performance is quite well during the early season, with 2 losses and 2 wins. The club is now on the midtable. I think that taking felix as a loan may give various options for lewandowski as we know that felix is good.
He just lacks of regular time to play in atletico madrid. Barcelona can give him more and it will be good for his career. He is also feeling so happy to play in his dream team.
I hope taking felix from atletico madrid would become a solution for lewandowski's problem with xavi's strategy.