Here's a good read if you got the time. It goes along way to explain exactly why M'bia (and others) are such a big success with Sevilla. Moneyball put into practice.
http://www.thisisanfield.com/2015/05/sevilla-monchi-moneyball-liverpool/
"Compare this to Sevilla’s signings in that time and the contrast is stark.
- Geoffrey Kondogbia, from RC Lens, £3.5m (2012)
- Carlos Bacca, from Club Brugges, £6m (2013)
- Kevin Gameiro, from PSG, £6.5m (2013)
- Marko Marin, from Chelsea, loan (2013)
- Vitolo, from Las Palmas, £3m (2013)
- Stephane Mbia, from QPR, loan (2013, made permanent 2014)
- Daniel Carrico, from Reading, loan (2013, made permanent 2014)
- Ever Banega, from Valencia, £2m (2014)
- Timothee Kolodziejczak, from OGC Nice, £2.5m (2014)
- Grzegorz Krychowiak, from Stade Reims, £5m (2014)
- Gerard Deulofeu, from Barcelona, loan (2014)
- Denis Suarez, from Barcelona, loan (2014)
(These are notable names from a long list of signings during that period. Transfer fees simplified and courtesy of TransferMarkt)
Each of these players joined for sensible transfer fees and became important players in manager Unai Emery’s successful side.
Bacca, for example, is La Liga’s fifth-highest goalscorer
this season, behind only Cristiano Ronaldo, Lionel Messi, Neymar and Antoine Griezmann.
That Sevilla are able to do so while offsetting big-money sales of the likes of Martin Caceres (£7m), Alvaro Negredo (£22m), Jesus Navas (£17.5m), Kondogbia (£17.5m), Gary Medel (£11m), Ivan Rakitic (£16m), Federico Fazio (£9m) and now-Liverpool pair Alberto (£7m) and Alberto Moreno (£16m) during that time and actually improve in the league and beyond is a testament to the model.
In the past three seasons, Sevilla have finished 9th, 5th, and (likely) 5th respectively, winning the Europa League once, with another final to come this season —
all while making around £32 million in transfer fees alone.
Next season they will likely look to expand even further. But how did they manage to do so?"