Jose Mourinho must mount a title challenge this season (Picture: Getty)

Premier League clubs were scrambling around on transfer deadline day to complete their business on the final day of what proved to be a record-breaking window.

Chelsea, Tottenham, Arsenal and Liverpool were all involved in deals in the last 24 hours of the window but Manchester United were conspicuous in their absence.

Jose Mourinho completed his business before the start of the Premier League season, spending £145million on Romelu Lukaku, Victor Lindelof and Nemanja Matic.

United’s bright start to the season means supporters are pretty happy with their transfer business but there are still questions to be answered.

1. Will United live to regret not paying Inter Milan’s £50m valuation for Ivan Perisic?

Ivan Perisic stayed at Inter Milan (Picture: Getty)

Mourinho spoke about a ‘surprise’ transfer target at the end of last season and it turned out to be Croatia winger Ivan Perisic.

The 54-year-old had made a personal check on the Inter Milan forward during Croatia’s clash with Ukraine in March and the Red Devils were confident of signing the 28-year-old.

However, Inter stood firm on their £50m valuation of Perisic and refused to bulk under the pressure from United.

Perisic would have offered something different to United’s current crop of wingers and his crossing ability would have been perfect for the likes of Zlatan Ibrahimovic and Romelu Lukaku.

Anthony Martial and Marcus Rashford have made good starts to the season so United fans will not be questioning Perisic’s failed move right now. But the pair are still young and inconsistent and Perisic would have safe-guarded United’s attacking options.

Mourinho said he wanted a ‘wide’ player so that he could play with three at the back. The Portuguese boss turned to a 3-5-2 formation in ‘big’ games against United’s rivals last season and Perisic would have proved valuable in the execution of these tactics.

2. Is Griezmann’s move still on next summer?

Griezmann wanted to move to United but stayed at Atletico (Picture: Getty)

United may have claimed otherwise, but Antoine Griezmann was the club’s number one attacking target at the start of the summer.

The club had laid the groundwork for Griezmann’s move to Old Trafford and were willing to pay his £85million release clause.

However, Atletico Madrid unexpectedly had their transfer ban upheld and Griezmann felt a debt of loyalty to the club.

Lukaku was signed instead of Griezmann (Picture: Getty)

The France international told United the move was off and signed a new deal with the Liga giants.

So the deal is off? Well, not exactly. Griezmann’s contract meant his pay increased dramatically but there was no increase to his €100m release clause.

It means United will be in the exact same situation next summer and they remain likely to sign Griezmann, who is still receptive to the move.

However, Lukaku’s arrival has given the likes of Henrikh Mkhitaryan a new lease of life and it remains to be seen if United will still have Griezmann in their thoughts.

3. Is Victor Lindelof ready?

Lindelof is yet to feature in United’s league campaign (Picture: Getty)

United kicked off their summer spending with the £30m capture of Lindelof from Benfica but it hasn’t been the smoothest of starts for the Swede at Old Trafford.

The 22-year-old was average at best during pre-season and hasn’t featured in any of United’s three Premier League games.

Mourinho says he will be given time to settle at the club and believes he will start in United’s opening Champions League group stage clash against Basel.

Lindelof’s early struggles mirror Mkhitaryan’s start to life at Old Trafford (Picture: Getty)

Henrikh Mkhitaryan was on the end of similar treatment from Mourinho last season but United can ill-afford to wait around for Lindelof to bed in.

Phil Jones has made a bright start to the season but the England defender remains injury-prone and Lindelof needs to be ready to partner Eric Bailly.

Time will tell whether he can succeed in his first season.

4. Where does Nemanja Matic’s arrival leave Ander Herrera?

Herrera’s future is under threat (Picture: Getty)

Few players benefited from Mourinho’s appointment last summer more than Herrera.

The Spaniard was shackled under Louis van Gaal and rarely given the freedom to produce the performances that led to him catching Sir Alex Ferguson’s eye when he was at Athletic Bilbao.

Herrera became a first-team regular last season and his energetic performances led to him winning the Sir Matt Busby Player of the Year award.

Herrera won the Matt Busby Player of the Year award in May (Picture: Getty)

However, Matic’s arrival has seen Herrera drop to the bench and it looks unlikely that he will force his way into the side while Mourinho plays a two-man midfield.

United’s kind opening fixtures haven’t called for a three-man midfield but any title challenge will have its rocky moments and Herrera could be called upon as the fixtures come thick and fast.

The question is, with one year remaining on his current deal, will Herrera be happy to sit on the bench as he enters his peak?

5. Has Mourinho got enough for a title challenge?

Mourinho could rue not making a fourth signing (Picture: Getty)

Above all else, this summer was Mourinho’s real chance to put his squad together for a title challenge.

All four of United’s signings last summer proved a success but Mourinho needs a similar hit rate this time around if United are to jump six places come May.

Mourinho’s now spent close to £300m since joining the club and he can no longer claim the squad is not his. United did well to emerge from last season with two trophies but anything less than a title challenge this season will be failure.

It’s no secret that Mourinho wanted four signings and his public claim that he’s happy with three may contradict his private feelings.

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