Ego? Hubris? No. Just, for him, sheer reality. Wilshere, now of West Ham, would walk into that Gunners midfield. He knows that. His friends and family know it. Indeed, the hold-overs from the Arsene Wenger era will say the same. There's no Arsenal midfielder superior to the former Gooner. Indeed this column would argue, of the 22 players on the Emirates pitch tomorrow, Wilshere remains the most talented of the lot.
But that's potential. What could be. There's also reality. The reality of a player who Arsenal had been trying to shift for almost two years. One loved. Respected. Inside the club. But also one who those who worked with him day-in, day-out felt needed a change for his own sake.
Unai Emery's no villain in this. He simply repeated the message that Wilshere had received 12 months previously. Only perhaps coming from a new face, it hit the midfielder much harder.
Wilshere knows if he had remained an Arsenal player this season. If he had simply signed his contract and just went with what he knew. For all he showed on the London Colney training pitches in preseason, the new man in the home dugout would remain unconvinced.
Emery offered Wilshere, by his own admission, the opportunity to stay. But there was a catch. Playing chances would be limited. The new manager was taking the team in a new direction. Wilshere could be part of it. But he was now only one of many.
It was the same message the midfielder received a year earlier from Wenger. While tomorrow has been billed as Wilshere v Emery, the England international knows he'd been on borrowed time at Arsenal for almost 18 months.
Recalling a chat a year ago he had with Wenger in the club gym, Wilshere said: “He said, 'I am going to be honest with you and at the moment we are not going to be offering you a contract, so if you can get a contract somewhere else, you can go'. Obviously I was not happy with that, but at the same time I was happy he was being honest."
Indeed, this column has learned Wilshere said much the same about Emery's frankness ahead of deciding to cut ties.
Again, Wilshere on Wenger's words: "He also said at the same time that if I did stay I had an opportunity to fight for my place, and if I performed well in the Carabao Cup and Europa League, I had a chance."
Which is the same, virtually word-for-word, that Emery relayed to the player earlier this summer.
There's been some ex-players. Indeed, some ex-teammates. Whom have taken aim at Emery for his handling of Wilshere. The player, to his credit, hasn't been among them. But it should be highlighted to those being critical that Emery's opinion was the same which Wenger held a year earlier. It was only due to injury - and a lack of interest - that Wilshere remained a Gunners player last season.
That's the reality. The reality of the player's career as it stands today. Two different managers. Indeed three if we include Gareth Southgate, the England coach. They've all passed over the chance to work with Wilshere long-term. For all the potential. It's no longer enough. Well, at least for some...
Tomorrow, you want to see Jack grab the game by the scruff the neck. To run the show. Dominate the boy Matteo Guendouzi. Outplay the inconsistent Granit Xhaka. Show us all that at 26, his best football is still ahead of him.
And it can be. Certainly, Manuel Pellegrini believes so. At Liverpool, the West Ham manager gave Wilshere the defensive security of Mark Noble and Declan Rice to do his thing. For Bournemouth, Pellegrini dropped Wilshere deeper, hoping to get him more on the ball. Beyond the two defeats, what the manager has shown is a desire to build his midfield around the club's No19. He wants to make it work. To give Wilshere every chance of proving those opinions at Arsenal - held well before Emery's arrival - wrong.
On paper. On reputation. Tomorrow should be Wilshere's day. Pellegrini will give him everything to make it so. And for those of us who are Jack fans, you hope reality this time falls his way.