The German coach penned a two-year deal with the French champions last summer, and an optional third one was included.

PSG have decided to trigger this additional year and the paperwork for the extended deal -- which would tie Tuchel to the French giants until 2021 -- has already been prepared.

Les Parisiens took the decision a few weeks ago and the humiliating defeat against Manchester United in the Champions League last-16 second leg last week has not changed anything.

PSG want Tuchel's stay to be longterm and the move is seen as another step towards that end.

Despite the United nightmare, the capital club's Qatari owners and the directors in Paris are happy with the work done by the former Borussia Dortmund and Mainz 05 coach -- off the pitch as well as on it.

Tuchel, 45, has added a new tactical dimension to the team, as well as forging a strong relationship with his dressing room which especially includes Neymar and Kylian Mbappe.

Sources say PSG feel that Tuchel's image, in terms of personality and communication, as well as the values that he transmits, are exactly what they want from their coach.

After 18 months of Carlo Ancelotti and three years of Laurent Blanc, as well as two seasons of Unai Emery, Tuchel is very good match for the club and that is why they are offering him a new deal.

PSG believe that the team has progressed under Tuchel, despite more Champions League heartbreak, and they are confident that he will move the club forward in the coming years.

Unsurprisingly, Chairman and CEO Nasser Al-Khelaifi backed his coach immediately after the United shock, saying "I have faith in him."

Despite unexpected Champions League and Coupe de la Ligue exits, Tuchel is enjoying his first season with PSG and very much sees himself at the club longterm.

"I want to stay here for a long time, grow and have success with this club," he said on Monday. "That is clear for me."

Tuchel's maiden campaign has been a rollercoaster of emotions, with recruitment issues both last summer and in January, a tough Champions League group stage, the toxic Adrien Rabiot case, Neymar's latest injury and fantastic league form but inexplicable defeats to both United and Guingamp (Coupe de la Ligue).

Nevertheless, Tuchel knows and acknowledges the merits of the PSG project, as well as its potential for copious success, trophies and, ultimately, glory.

Sources have indicated to ESPN FC that Tuchel could sign his new deal during the upcoming international break, or once PSG have wrapped up the Ligue 1 title -- possibly as early as next month.

On the other hand, Tuchel's new contract is not good news for PSG sporting director Antero Henrique as the two men do not get on and do not agree very often.

It looks more and more unlikely that the Portuguese will still be at the club next season, as sources told ESPN FC earlier this year.

Should Henrique's departure be confirmed, sources say Tuchel would then be heavily involved in the choice of his replacement -- strengthening his position even more.

Meanwhie, later on Thursday Rabiot opened up about being frozen out of the senior setup since the end of 2018 and stressed that he never wanted to be in his current situation.

Without an appearance for the Ligue 1 giants since last December's 4-1 Champions League group stage win away at Red Star Belgrade, the France international has had to suffice with training sessions since negotiations with PSG over a contract extension broke down.

"Of course, it has been hard not playing these past 3 months," said Rabiot to InfoSport+ outside of the French champions' Camp des Loges training centre. "However, it was not my choice.

"This situation is not my choosing -- I am at the club's disposal. Everything is fine, I am in shape. If I could play, I would, but the leaders have decided otherwise."

Rabiot's contract runs out this summer and the 23-year-old was recently blasted by Henrique for being caught partying after PSG's loss to United last week.

Despite that and his reported consequent suspension, Rabiot insisted that he was disappointed that his formative club threw away a two-goal first leg lead from Old Trafford.

"Despite everything that is said, I am still a PSG player," he said. "I am under contract and with my teammates.

"Going out of the Champions League to United was very disappointing, again, as it is not the first time like this."

Sources recently confirmed to ESPN FC that Rabiot has not replaced his mother Veronique as his agent in an effort to secure himself a free transfer move to a European giant.

The source added that Rabiot still sees himself playing for a different club next season but is no closer to knowing which one it might be -- something that is still yet to change.