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As warnings go, it was stark. 

Brendan Rodgers laid it all on the line for Reo Hatate. Having left the Japanese midfielder out of the team for the opening two Scottish Premiership matches of the season, the Hoops boss was asked to explain his decision in the build-up to the win over Aberdeen at Pittodie.

"I’ve mentioned before, it’s not in my contract to play any player," he said. "He (Hatate) has got three years left on his contract so there’s no rush. It’s a new cycle, a new manager and he has to prove himself. I’m not really worried about what’s said or not, I’ll play the team I see with the best energy, mentality and efficiency with how we want to work.

"There’s no doubt Reo is a talented player, but there are other talented players in the squad. If players aren’t playing, I’ve been open and honest with them about where we’re at, how I prepare a team, when I tell them the team, and when they’re not playing how they’ve got to respond.

"Reo’s been really good in training. He didn’t play but he came into the game. He knows areas he needs to work on to play for me, and the structure of how I work. He’s responded really well in training and will absolutely be a player we need over the course of the season. Look, you never expect players to be happy if they are not playing. That’s just the way Reo is too.

"Even before a ball was kicked I could see he has that style and way about him. But he’s a good guy, there is no question of that. There are none of them here who I’d say there is a red flag in terms of their attitude or anything like that. They are all so professional in their work and do everything correctly."

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Now Hatate's body language, or lack of it, has been put fiercely under the microscope following Rodgers' team selections. All of a sudden, the best midfielder at Celtic, and arguably in the country, is facing criticism.

Complaints by some that he looks unhappy, wants to leave and has not been the same since Ange Postecoglou departed the club are all without foundation. It feels unfair to try and understand what a player thinks purely from his lack of celebration after scoring a sensational goal against Athletic Club and a video of him walking unmoved past fans without responding to their requests for a selfy.

During pre-season, and after having watched Jota clinch a similar £25 million move to Al-Ittihad, the Japan international was asked what could be next for him in his career trajectory. He said: "Playing at a high level such as the Premier League It's a once-in-a-lifetime stage, so if I can play, I'd like to take on the challenge. But right now, the top priority is to do what I need to do in the team I'm in, so I'd like to do my best. Before playing in the Champions League, it was a stage I longed for. Now I want to compete there again. I think it was a good experience."

If Hatate wants to sample playing in the Champions League again, then few clubs other than Celtic will offer him that chance. He may well be tempted by the fruits of another elsewhere before the transfer window shuts. 

The Brighton & Hove Albion link doesn't seem to be going away anytime soon and is hovering like a... seagull eyeing food - isn't it? Hatate is a sublimely talented and gifted footballer who was one of the first names on the teamsheet under Postecoglou. That was a given.

He supplied nine goals and 11 assists last season and was a vital cog in the green and white machine that swept to a double and a treble under Postecoglou over the last two years. Many supporters are puzzled as to why he has not kicked on under Rodgers since he took over.

The 50-year-old spelt it out in layman's terms what Hatate needs to do to become a permanent fixture in his Celtic team. The midfielder's football rise has been meteoric, and in his defence, some of the latest criticism of him is over the top, but Newsflash; Celtic are under new management. Players will need to shape up or ship out under Rodgers even if they are extremely popular but only if the price is right, of course. See Jota. Ironically it was Postecoglou who warned the fans not to get too attached to their heroes.

With Tottenham Hotspur having recouped £100 million plus for selling Harry Kane to Bayern Munich, the rumour mill is running rife that he may come calling north of the border with the likes of Hatate on his shopping list. Such an approach from the North London club would not be welcomed and it should be rebuffed at every turn, but it certainly will not faze Rodgers one iota.

Two years ago, Postecoglou started to build a beautiful house in Glasgow's east end. Rodgers has now taken up the managerial cudgels and does not need players who may wish to cause a fight in an empty one, especially when the treble winners are trying to build momentum ahead of the Champions League group stages in September.

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With three years left on his current deal, there are no guarantees that Hatate will even see the remainder of that contract out. At his official unveiling as Celtic manager Rodgers said: "I've signed for three years and I guarantee I'll be here for three years unless I get emptied before that, as they say up here."

That same rule applies to every Celtic player. Hatate included.