Only 13 minutes had been played when Wayne Rooney lit up this title coronation. From near the halfway line came a Hollywood pass that fell like a Joe Montana hail mary on to the left boot of Robin van Persie. Brad Guzan, the Aston Villa goalkeeper, became a spectator as the striker's sweet volley produced his second goal and, as Old Trafford went berserk, Rooney was given the thankyou of a fireman's lift by the Dutchman.

As a riposte to those who wonder if the bell tolls for Rooney's Manchester United career it was pure box office. Yet there is no escaping the sense that this is the season of reckoning for Rooney. One in which his fitness has been questioned, he was dropped for the season's grandest night – the Champions League last-16 second leg here against Real Madrid – and Van Persie has taken over as the star turn.

So when the answer to the evening's first big question came in the affirmative it was to Rooney's relief. Yes, he was in the XI Sir Alex Ferguson sent out in the hope of clinching United's 20th title and the manager's 13th with the club.

Yet Rooney's selection came with a "but." Just as at Stoke City and West Ham United in the past two outings, his place in the forward line was again usurped. While Van Persie, as expected, was the focal point, the "10" berth went to Shinji Kagawa, as it had done at Upton Park.

To see Rooney alongside Michael Carrick in midfield was to wonder if this was a function of his total football abilities or the start of a long-term move from Ferguson. When Van Persie completed a 33 minute hat-trick – having opened the scoring inside two minutes – it was Rooney's ball that initiated the move. Yet when he joined the gang of jubilant team-mates it felt like the wrong picture: Rooney is usually the centre of a goal celebration, the focus. Not on the margins.

For Rooney's selection to be a subject for bar-room debate was unthinkable even at the end of last season. Then, the campaign closed with United forced to swallow the bitter taste of Manchester City snatching the championship with a swish of Sergio Agüero's boot. Yet Rooney finished with the goal that beat Sunderland to ensure City were pushed to the death as he added 35 more strikes to his United tally to confirm his status as top dog.

Van Persie's arrival changed that order, and suddenly Ferguson was describing him as his No1 striker at Old Trafford. The cut leg that Rooney suffered in the late August win over Fulham did not help: it caused him to miss a month of action, and for the manager to start a series of dispatches regarding the need to watch his fitness.

An augury of this shift came in the serialisation of Rooney's book in September. In an extract perhaps more honest than intended, he wrote: "Physically I've taken a bit of a battering over the years. When I get up in the morning after a game, I struggle to walk for the first half an hour. I ache a bit. But football has had a massive impact on my body because my game is based on speed, power and intensity."

Here was an admission to confirm Ferguson's sound instincts that Rooney's cruiserweight physique allied to a decade at the business end of the game would need careful monitoring as he moved towards his thirties. But though it was 20 October before Rooney registered a first United goal, his count of 12 goals in 24 league outings – Van Persie, with his latest hat-trick, has 24 in 33 – is still the kind of total a £250,000 a-week performer should be returning.

As the clock ticks down to two years left on these terms, whether United hand him another super-sized deal will be one of the summer's narratives. April began with Zlatan Ibrahimovic claiming that Paris Saint-Germain, bankrolled by the Qatar Investment Authority billions, should be Rooney's destination should he depart. "If he wants to be part of the best project in football, then there is only one club to sign for. I can understand why the owners are interested in Rooney," the Swede said.

By all accounts, though, there have been no approaches (yet) from PSG. And, Rooney wants to continue at United. So if a bid is to be lodged it will come down to how much Ferguson wants to keep him. The jury may still be out: the last sight here was of Rooney being substituted on 72 minutes.