For the first time in seven years, Manchester United declined the thrill of a deadline day signing, opting to end this window with the same discipline that has driven their decisions since June.That climax has, though, led to disappointment in those fans who feel the club missed an opportunity to build on Michael Carrick’s work last season by really strengthening the side.Crucially, United go into the rest of the campaign with Luke Shaw as the only specialised senior left-back. No new face arrived in a position that was given plenty of internal consideration. Ultimately the club have kept their powder dry for another attempt at signing Lewis Hall from Newcastle United next summer.United did have opportunities to bring in competition for Shaw, even in the final 24 hours, to add to the list that includes Senne Lammens, Manuel Ugarte, Sofyan Amrabat, Antony, Cristiano Ronaldo, and Edinson Cavani as deadline day deals.United made a check with Manchester City in the afternoon on Rayan Ait-Nouri, who had been offered to them by an agent a few days ago. It would have been a dramatic and rare transfer across town, but City told United a loan would only be possible with an obligation-to-buy reaching several tens of millions. United had no interest in a permanent move so walked away.United placed a call with Jorge Mendes to check on the conditions of Alejandro Balde, who was an unused substitute for Barcelona against Rayo Vallecano on Monday. But talks for the 22-year-old did not progress. United had stepped away from a proposal for Ian Maatsen at Aston Villa.There is a thin line between exploring options as a precaution and acting desperately but United did not press the panic button and believe they have cover for Shaw in the shape of Noussair Mazraoui and Diogo Dalot, who can switch from the right, and in emergencies Lisandro Martinez, Carlos Baleba, and Patrick Dorgu, who is seen as a left-winger. Diego Leon, bought for an initial £3million ($4.05m, €3.5m) rising to £7m last summer, is not in this conversation. He is 19 and acclimatising to under-21s football.United asked City about a deal for Rayan Ait-Nouri (Simon Stacpoole/Offside/Offside via Getty Images)Harry Amass is still in the building after United held firm on spending in that position. Amass, 19, had interest from more than a dozen clubs across the window — including Sporting CP in Portugal, Wolfsburg in Germany, Celtic in Scotland, as well as Championship sides Stoke City, Birmingham City, Millwall, Queens Park Rangers and Burnley, who saw a bid worth around £3.5million rejected. United wanted £6m.Late on United decided they could countenance a loan, with Derby County making a proposal, but they chose to keep Amass.The wisdom of United’s decision will be tested if Shaw gets injured.They did try to sign another midfielder on deadline. United reopened talks for Louis Page, the 18-year-old at Leicester City, and advanced to a stage when a deal looked possible. The price rose sharply to more than £10m, which United entertained, before an impasse occurred over Leicester’s valuation, thought to be £12m plus £3m.Page was named by Russell Martin in Leicester’s starting line-up for the League One visit by Plymouth Argyle and that was the end of the matter. Page played well and United are expected to revisit the situation. Page wanted to join United, having turned down Arsenal in the summer.Another deal that appeared close but fell through was Everton’s loan bid for Joshua Zirkzee, amid uncertainty over Folarin Balogun’s move from Monaco. Everton first made contact with United at 5pm and made an offer at 8pm. United were open to Zirkzee leaving — he has been pushing to leave to play — but decided it was too late to source a replacement. United sources suggested the proposal was worth less than the reported £10m including loan fee and wages. Some players felt a new centre-forward to share the load with Benjamin Sesko was needed, allowing Matheus Cunha and Bryan Mbeumo to play more in their best positions.So United ended the window with three new midfielders and a deputy goalkeeper, inviting the question of whether, to use Carrick’s words, they have “pushed the boundaries”. The day after United faced Leeds United in Dublin, Carrick said: “There’s one or two areas where we’d like to improve. We are pretty clear that we need to keep pushing. There’s certain things we want to try and do, but it needs to be right.”United went on to sign Baleba and end their spending at £155m, around £50m less than 12 months ago under Ruben Amorim despite now being in the Champions League.The Athletic has spoken to multiple sources, who all spoke on condition of anonymity to protect relationships, across the window to tell the story of a third summer under Sir Jim Ratcliffe’s leadership, with a third different man in the dugout, which includes: