When you are 18 years young, the tests come hard and fast. Last Monday's may have been straightforward enough: sign this contract, Jack, and Arsenal will pay you more each week for playing football than your old schoolmates earn in a year. Club sources say reports of £50,000 a week were exaggerated but, as Jack Wilshere admits, appending a signature to that particular document was "the easiest decision I've ever had to make".
Two days later, in the far east of Ukraine, which is a long way from home in Hitchin, comes a trickier challenge. Arsenal are playing an important tie in European football's most prestigious competition, in front of almost 50,000 partisan fans who have been told by their club coach that Wilshere should have received a red card in the previous meeting for "a violent foul". Not only that, but injuries and Arsène Wenger's rotation policy mean that he becomes the senior man in terms of experience in the key defensive midfield partnership required to protect the Arsenal back four.
Half an hour after a game against Shakhtar Donetsk that went badly wrong, bringing a first defeat after five successive victories, Wilshere is downcast but, with the innocence of youth, desperate to right that wrong, preferably against Newcastle United at the Emirates this afternoon.
He is available for the Premier League again after a three-match suspension, a self-confessed lesson learnt. The referee for the game against Birmingham City last month took a dimmer view of a late tackle on the lanky striker Nikola Zigic than the Champions' League official against Shakhtar, and the result, rightly, was a sending-off. He was forced to sit out matches against his boyhood favourites West Ham, Manchester City and Newcastle in the Carling Cup.
The next encounter with Zigic is due at St Andrew's on New Year's Day, Wilshere's 19th birthday. His Shakhtar victim, experienced Czech international Tomas Hubschman, was waiting on Wednesday and left Wilshere in a heap on the damp turf as the home side broke away to set up their equalising goal. Another lesson learnt, and no bleating about either that or the red card.
"Obviously I am going to learn from that," he said. "I was playing week in, week out, then I was stopped for three games. It was frustrating and boring. I look back and it was stupid. It was the last minute and it was a bad touch, I went into the challenge and that was it.
"It is important to learn to look after yourself but there is a line and maybe I went over that line at that time. It was a mis-timed challenge, I have learned from it and now I have to move on. I am only 18 and at this time in my career it is all about learning. I have said it before, playing with people like Cesc [Fabregas] and Samir [Nasri] you are going to learn off them."
For Fabregas and Nasri in the Arsenal side, read England's Steven Gerrard and Frank Lampard. Since the opening international of the post-World Cup season, Wilshere has a full cap and he can reasonably expect another one against France in a fortnight's time. His eventual role for club or country has yet to be defined. Wenger believes he will end up playing either in central midfield or behind the striker(s). At present he is used in a more defensive role, from which he can and will nevertheless break forward.
Modelling himself on Arsenal's current Head of Youth Development, Liam Brady, he has been well-served by the club he joined aged nine, believing that a loan spell at Bolton last season was of particular benefit. "It made me realise what Premier League football is like week in, week out. It is not like reserve games when you are developing. You have to go out and get the three points.
"I owe a lot to [Bolton's manager] Owen Coyle. He was great to me. He played me. He put his faith in me. I live at home with my mum and dad but it was different up there. I was on my own most of the time. It made me realise what football is about. And it was different because of the way they play. But it is Premier League football and that is what you want."
It is what he wants this afternoon. But, being polite and unpresumptuous: "It is the manager's decision and I will just have to see."
Arsenal v Newcastle United is on Sky Sports 1 today, kick-off 1.30pm