There have been some huge twists on deadline day over the years. Who could forget Newcastle United selling Andy Carroll to Liverpool when the Magpies' number nine was ready to sign a new contract with his boyhood club?

However, there was no prospect of Newcastle re-entering the race for Marc Guehi at the 11th-hour after Spurs saw a huge bid turned down for the Crystal Palace captain over the weekend. The message throughout the mid-season window has been consistent. There is a will at all levels to strengthen the side, but Newcastle are unable to do so due to PSR restrictions.

Supporters have wondered why that is the case. Newcastle, after all, were able to make huge offers for Guehi last summer and the black-and-whites ended the window with a healthy profit. However, Eddie Howe insisted talk of formal bids of £60m-£65m for Guehi was 'far in excess of potentially what the reality was' and the Newcastle boss alluded to the fact the Magpies would have had to potentially sanction further departures if the England international had arrived.

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"I'm not going to sit here and explain PSR because I don't even understand all of it, but it's not as clear as everyone will make out," he said last month. "There's not a pot of money there waiting to be spent. It's all about the 30th of June and making sure you comply by that date.

"Obviously, if you spend money, then you have to recoup it at a later date, so that doesn't explain anything, does it? But it does in my head."

Rather than bringing anyone in during the mid-season window, Miguel Almiron was instead sold last week in a deal Newcastle 'needed to do' for PSR reasons. A replacement will not follow this month because complying with the Premier League's financial rules is Newcastle's 'first port of call' in Howe's words following a bruising summer.

Senior figures throughout the club have repeatedly stressed Newcastle do not want to find themselves in the position they were in back in June when the black-and-whites had to scramble to raise funds at the 11th hour to avoid a PSR breach. Paul Mitchell may have arrived after the event, but even the sporting director admitted that Newcastle had 'got away with it by the skin of our teeth'.

"We have to make sure that we don’t end up back there any time soon because we just survived," he said earlier this season. "That’s why we are really analysing strategy and making sure we’re fit for purpose. Global reach, player profiling - all of these things will come together to help us avoid a similar situation in the future."

Trading will also become a key part of Newcastle's strategy after the Magpies raised just £12m profit on disposal in the previous three-year cycle. Although Newcastle won't want to lose key players like, say, Brighton have over the years, the Seagulls have been smart traders, which has enabled the club to reinvest and sign a highly-rated young striker like Stefanos Tzimas on deadline day.

The huge profits made from the sales of Moises Caicedo, Marc Cucurella, Ben White and Alexis MacAllister have naturally grabbed the headlines over the years, but Brighton also secured £25m for a fringe player like Deniz Undav last summer. This is the sort of fee Newcastle need to bring in more regularly and Lloyd Kelly's impending move to Juventus feels like a start in that regard.

Kelly offered cover in two positions, but made just four league starts for Newcastle. If the defender was to remain rooted to the bench for the rest of the season, while on a decent wage, would that be the best use of resources? Could Newcastle demand £20m in the summer if Kelly went another few months without playing regular football when there are going to be even more options available to clubs on the market by then? Was there an element of the stars aligning this month given what an opportunity it was for Kelly and how injury-hit Juventus desperately needed a new centre-back?

Kelly's departure also improves the club's financial picture this summer and it is worth noting Newcastle held an interest in a number of centre-backs even before the 26-year-old's departure. Newcastle's recruitment team did all the homework - from holding talks with the players' agents to carrying out character checks - so that the Magpies were not starting from zero in case the club's financial picture dramatically changed. Although that groundwork did not pay off in the mid-season window with, say, Abdukodir Khusanov or Juma Bah, who joined Manchester City, it could pay dividends with other targets in the months to come.