Paul Pogba is an enigma. The Manchester United midfielder arrived at Old Trafford 12 months ago for a record fee of £89.3 million, yet as he prepares for his second season with the club, the unanswered question about the Frenchman is precisely this: What does he bring to the party?
He is not a box-to-box powerhouse in the mould of Yaya Toure, he does not score the goals of a Steven Gerrard or Frank Lampard and he does not display the authority of Michael Carrick. Overall, he has yet to show he possesses the heroic leadership qualities of his great United predecessors, Bryan Robson and Roy Keane.
Yet despite everything he is not, Pogba is clearly something special. United fended off interest from Real Madrid and Barcelona to sign him from Juventus, four years after allowing him to leave Old Trafford for just £800,000, and he is a player of undoubted quality.
He is tall and rangy -- when in full stride, he gallops through midfield like a thoroughbred. He's bold and adventurous, can boot passes 60 yards and at age 24, is entering a period of his career that could see him emerge as the world's leading midfielder.
But his first season back at United left everybody expecting -- and wanting -- more. While he helped United win two trophies in the EFL Cup and Europa League, the outstanding midfielders in the Premier League last season were N'Golo Kante, Victor Wanyama and Dele Alli. Jose Mourinho's expensive star signing was not among that group.
Nevertheless, Pogba's performances on United's preseason tour of the United States suggest the midfielder is beginning to blossom into the dominant figure that Mourinho needs him to be.
He began to look like the cornerstone of the team rather than the window-dressing.
He arrived at United last year in mid-August following a busy summer that saw him play in France's run to the Euro 2016 final.
As a result, he missed out on a preseason campaign, and occasionally looked like he could've used the break he passed up on to play in the Euro Cup.
Although he ended the season with nine goals in 51 appearances, he has the ability and ambition to double that goal tally this term and become the centre-piece of Mourinho's team.
Carrick may have been handed the captaincy by Mourinho following Wayne Rooney's departure to Everton, but Pogba is being groomed to become the next owner of the armband.
"He's certainly got the presence, character and belief to pull it off," Carrick said about Pogba during the tour of the U.S. "I'm sure the manager is planning a long way behind me, for someone to take on that mantle, and he's probably in that bracket where you'd say: 'Yeah, he can be a future captain.'
"Obviously Paul is a confident lad, so over time he's going to be a great player for this club. He's had a year to adjust, I know he was here as a kid, but a lot has gone on since then and he's played a lot of different football since then.
"So to come back with all the scrutiny he had last year and everything surrounding it, it was probably always going to be one of those years where you take time to settle in and improve. I think we've seen the improvement and we'll see it again next season."
Mourinho has described Pogba as the "leader of the young guys," but some within the club believe that in order to truly assume that role, he must find maturity off the pitch as well as on it.
Sources at United have told ESPN FC that Pogba is a "young 24", and that he is not yet clear-headed enough to become the team's leader.
That presents something of a problem for Mourinho. A dressing room source admitted the dynamic within the squad has changed over the past 12 months in that the old leaders -- Rooney, Ashley Young and Carrick -- have all either moved on or become peripheral figures, leaving Pogba and (last season at least) Zlatan Ibrahimovic to become the figureheads.
Though Carrick remains captain, he would do well to play in half of United's game this season, while Ibrahimovic has been released and will spend the next six months overcoming a cruciate ligament problem.
So Pogba is in line to become the main man, though some doubt he is ready for the role. Having given Carrick the captaincy, Mourinho perhaps shares similar reservations.
Publicly, though, the United manager is Pogba's biggest supporter, offering only positive comments about the player. "I would say he's the leader of the young guys," Mourinho said recently. "He is probably the oldest of the young guys.
"He has big experience at such a young age, but at the same time, he's still the kid that came from the academy.
"With his experience, though, and with his status and with his quality on the pitch, where he is also a key player for us, I think Paul has the conditions to be in a couple of years such an important guy in the club."
United cannot afford to wait a couple of years for Pogba to become the club's undisputed leader. That needs to happen now.
Rio Ferdinand was not alone last season in criticising Pogba for his focus off the pitch. The former United captain raised doubts over Pogba's social media obsession, insisting there was a time and a place for everything.
"Did he see my point?" Ferdinand said to ESPN FC earlier this year. "I don't know, maybe only time will tell.
"But he's a commercial company's dream -- he smiles all the time, rain or shine he's happy; he's very animated in what he does and he's very viable in that commercial sense.
"He's perfect, he's a dream for those guys and he's going to do it. And if he's got the confidence to carry it off that's down to him."
Ferdinand was arguably the mould-breaker in terms of social media presence in English football at the turn of the decade, emerging as the first high-profile footballer to take to Twitter and Instagram.
But by that stage, Ferdinand had won a bucketful of Premier League titles along with the Champions League, so he had already walked the walk.
Pogba has all the attributes to do the same, but United need him to become as dominant on the pitch as he is visible off it.
This is the season where they need him to burst box-to-box like Toure, score goals like Gerrard and Lampard and develop the authority of Carrick.
Only then will he be able to target the pedestal on which Keane and Robson sit at Old Trafford.