Of all the players who could leave Manchester United this summer, Ander Herrera was probably the least convenient for Ole Gunnar Solskjaer.
Midfield was arguably where United were best stocked, albeit with some improvements needed from Solskjaer's existing players for next season.
But Herrera's decision to leave has left Solskjaer with yet another position to fill this summer, as the Spaniard's energy and leadership will need replacing quickly.
In theory, Paul Pogba, Nemanja Matic and Fred should be able to provide that - ably assisted by Scott McTominay and Andreas Pereira - but none showed those qualities on a consistent level this season and Solskjaer would be wise not to assume they will all improve at once next campaign.
At the same time, Solskjaer's midfield is not far away from being complete - especially with some slight improvements from his fringe men to increase the competition.
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But with Herrera gone, United still have to dip into the transfer market to find a suitable replacement, to go alongside a centre-back and winger already on the growing transfer wish list.
It also makes sense to replace him quickly and avoid a transfer saga like last summer's chase for a defender, and there is a ready-made option available that solves multiple problems.
With Herrera seemingly set to join PSG, his arrival will push want-away Frenchman Adrien Rabiot further down the pecking order. Rabiot is available on a free transfer, and United won't have a better opportunity to add quality to their squad at such relatively little cost.
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Rabiot has Champions League experience, and will have a point to prove after being shunned by PSG this season. Solskjaer wants to cultivate a competitive atmosphere at Old Trafford and Rabiot would be able to buy into that.
Going against United is the fact that Rabiot, 24, is reportedly wanted by a number of European clubs, so they must act quickly. They cannot offer Champions League football either - so Solskjaer must persuade him with the prospect of regular football.
He may not be the ideal choice if United had time to pick a perfect midfielder from one of Europe's best clubs, but Solskjaer doesn't have that luxury this season. He would be a pragmatic signing that allows United to focus their energies elsewhere this summer.
With so many other priorities to solve in the transfer market, Rabiot presents a relatively cheap solution to an unwanted problem that will allow Solskjaer time and funds to chase the big name signings he wants elsewhere in the team.
An opportunity like this may not come around again - and could save the club millions. United cannot afford to let chances like this pass them by.
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