Man City were right to break Pep Guardiola policy with Riyad Mahrez decision

When it comes to transfers and contract negotiations, Manchester City have principles from which they very rarely stray.

Generally speaking, City won't offer above their valuation of a potential signing — see Harry Maguire, Jorginho and Frenkie de Jong — while players who want to leave are free to do so, provided they attract a suitable offer.

Sticking to guidelines like these ensures that City are responsible with their spending and don't waste resources, while also keeping a healthy dressing room environment for Pep Guardiola and his players to work with. However, there is one general rule that City have recently broken — and for good reason.

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On Friday Riyad Mahrez penned a two-year contract extension at City. The Algerian winger had entered the final 12 months of his previous deal, but has agreed to fresh terms to commit his future at the club until 2025.

Given that Mahrez was City's top scorer last season with 24 goals in all competitions, while also matching Kevin de Bruyne's tally of 33 direct goal contributions, perhaps it's not surprising that City were keen to tie the attacker down to new terms. However, the fact that Mahrez turned 31 in February does make this unusual. With the obvious exception of Fernandinho, City tend not to hand out new contracts to players who are the wrong side of 30 and whose deals are close to expiring.

The rule of thumb is that once players pass 32 they start to slow down, so they aren't able to deal with the physical demands placed on them by Guardiola's system. Pep's City can't afford to carry any passengers.

Clearly though there are exceptions. Fernandinho was clearly past his best when he signed