Ruthless. Adjective: having or showing no pity or compassion for others. Merciful. Adjective: showing or exercising mercy; bringing someone relief from something unpleasant.

How is it then that Celtic boss Ange Postecoglou managed to display both of these traits with regard to Moritz Jenz? You can't be ruthlessly merciful, can you?

Well, actually, you can. Only though if you listen and pay close attention to the Hoops manager and what he says at all times.

Here's what the Aussie said after the AGM in December: "We can make gains by being aggressive and agile in the transfer market. Other clubs our size are very agile. Every couple of years they’re regenerating and we need to maximise the greatest amount of revenue into the club. We need to push forward aggressively over the next two to three years and keep growing. Our approach has to be aggressive.

"We will need to move players around to make gains. We have to maximise our squad to get the greatest revenue for the club. I'm comfortable with that. It will be unsettling for you guys, as you'll have favourite players, but we need to be wise."

Celtic's first-team squad consists of 39 players including loanees and excluding the B-teamers with shirt numbers. It was always inevitable that some would move on.

First, it was Josip Juranovic, then it was Jenz. The Giorgos Giakoumakis transfer saga continues to intrigue and frustrate the life out of everybody, doesn't it?

Postecoglou re-iterated his stance not long before Juranovic chose to sign for Union Berlin last weekend when he said: "I said at the AGM we have just got to be really agile and aggressive in the transfer market if we want to make the gains we want to make. I get that it is unsettling and disconcerting, particularly for our supporters, because they love these players, and I totally understand that.

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"My role is to try to make decisions that I think are best for us and our continued growth as a football team, and realising when an opportunity comes along we have to be ready to take it. That's what we did with Josip. I don't think there needs to be winners and losers out of this."

Celtic are never going to be the losers in any of this. Not with Postecoglou and Michael Nicholson pulling the strings when it comes to football and financial decisions merging.

That brings us neatly back to Jenz. The 23-year-old was a regular in Postecoglou's side up until the World Cup finals in Qatar in December.

He didn't start a match for Celtic thereafter. He made 11 Premiership starts for Celtic and even grabbed two goals in his first two appearances. A crucial headed goal against Ross County that helped seal a 3-1 win in Dingwall and a brilliantly executed overhead kick against Kilmarnock in a 5-0 romp at Rugby Park both in August.

The return to fitness and form of Swedish central defender Carl Starfelt knocked Jenz down the pecking order. Postecoglou has been reticent to rotate his central defensive partnership. Again, if you listen to what the manager has to say, then he signposts and roadmaps this all out. He simply doesn't like chopping and changing his central defensive personnel if he can help it.

The fact that Carl Starfelt and Cameron Carter-Vickers don't lose league matches whenever they are partnered together tells its own story. When you add the recent acquisition of Japanese left centre-back Yuki Kobayashi into the mix then the first-team picture frame was already shrinking for Jenz.

The German was simply not going to play first-team football. That was the very reason he left FC Lorient in the first place: to seek regular game-time.

Celtic Way:

So Postecoglou was ruthless in the fact that he cut Jenz's season-long loan short and jettisoned him from his Hoops team. But you could also argue that it was merciful to an extent.

Now it's not all been about 'big bad Ange'. Jenz played and started six out of six Champions League games for Celtic. He would not have got that kind of exposure elsewhere. It's the kind of exposure and experience that led the player to conclude a deal with Bundesliga side Schalke, struggling at this moment though they may be.

So Postecoglu was also merciful. It showed that he was not going to entertain players - who may have been regulars at a given juncture - hang around the club if they are surplus to requirements. In this case, Jenz was simply not needed.

But this is where the whole perception of the ruthless narrative can be challenged to a degree. Postecoglou has clearly been downright open and honest with the player. He has been aggressive and agile in the fact that Celtic would not be exercising the option to buy clause in Jenz's contract.

The club tried, but they didn't want to buy. They used that situation to their advantage. Vitally, Postecoglou also opted not to keep a player at the club simply to cover himself with an extra insurance policy in that area of the pitch. By being merciful, he has allowed Jenz to go and play elsewhere.

It makes perfect sense. As the manager said, it doesn't always have to be about winners or losers. Unlike, say, times of old with players like Cristian Gamboa or Marvin Compper.

Those days are gone though. Long gone. They are no more. Postecoglou and Nicholson will see that to that. Aggressive and agile, remember?

The Celtic clearout has already begun in earnest under Postecoglou's watch. Sure, he'll need a ruthless streak if he's going to trim the excess fat off an already bloated squad, but that doesn't mean to say that the Aussie doesn't care about his players.

Cutting Jenz loose was a merciful act by a manager who knew that the player had a lot to offer someone - just not Celtic.

Football management is full of dark arts and Postecoglou is fully aware that he will have to make unpopular decisions regarding popular players moving forward.

Once more: "I get that it is unsettling and disconcerting, particularly for our supporters, because they love these players, and I totally understand that. My role is to try to make decisions that I think are best for us and our continued growth as a football team."

Even Jenz got the memo. His emotional and heartfelt goodbye to Celtic paid a wonderful tribute to the Aussie individually.

Jenz said: "A massive thank you to Mr Postecoglou for giving me the opportunity to play for this fantastic club. It has been an honour to work with him and his team."

The Aussie was certainly ruthless when it came to the contractual football matter surrounding Jenz in midweek but he also proved that he can be merciful too. He doesn't have a dark heart.

It's a tough gig being a ruthless managerial assassin who can also make merciful, level-headed business decisions.

With regards to Jenz, Postecoglou showed that he is a very wise man indeed. Celtic are in extremely fair managerial hands.