It is safe to say that Celtic fans are not happy with how the club have handled their business this summer. That was clear from the most recent friendly at Parkhead.

The Hoops played to a largely empty Parkhead, as the game ended in an uninspiring 1-1 draw against Middlesbrough. Martin O'Neill's season are still searching for their first win in pre-season.

While it is never recommended to read too much into pre-season results, the lack of wins is starting to become a worry with the new season just two weeks away.

Celtic have been going about their business, but it has been quite disappointing. The only signing has been Camilo Duran, who did score his second goal for the club in as many pre-season outings today.

Other than that, there has not been anything of note. It has already been confirmed that Kelechi Iheanacho and Marcelo Saracchi won't be returning. And now, a highly-rated defender has completed a move away as well.

Celtic have now officially announced the departure of Maik Nawrocki, who has joined RC Lens on a permanent basis.

Anthony Joseph shared some further details on the move, confirming that Nawrocki has penned a four-year contract with the French club.

There will be a mixed reaction to the news. Some feel that it was time for the two parties to part ways and Nawrocki did not have a future at the club.

But then, Celtic do need another centre-back. And Nawrocki has impressed in the past whenever given a chance.

While Nawrocki barely featured under Brendan Rodgers, perhaps the story could have been different with O'Neill as manager. At least that was the hope for many.

The fact that he has joined RC Lens, second in Ligue 1 last season, just goes to show how highly he is regarded in European football circles. In the long run, Celtic might end up regretting how they handled the Polish centre-back's time at Parkhead, if he ends up proving to be a success in the French top flight.

READ MORE: Anthony Joseph Confirms Celtic Transfer News

For Celtic, the key is to sign some ready-made quality this summer and find a way to win back the supporters. They simply have not done enough so far in this window, not even close.

Earlier in the window, there had been links with some centre-backs, but those have faded away over time. Right now, it looks like the club might be more focused on their options going forward and in the middle of the park.

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