The figures show that, with Isco in a four-man midfield, Real Madrid score as many as in a 4-3-3, concede fewer - and win more matches.
All the indications are that Real Madrid's beleaguered coach, Julen Lopetegui, is to place his faith in Isco and send his side out against Barcelona with a midfield four of Casemiro, Luka Modric, Toni Kroos and the former Málaga man.
The 4-4-2 formation is one that has brought Madrid success in recent times, with two clear examples: it was the set-up used by Lopetegui's predecessor, Zinedine Zidane, in the 2017 and 2018 Champions League finals, with the midfield operating in a diamond shape that sees Casemiro sit in front of the centre-backs, Modric and Kroos operate in the right and left-hand channels and Isco positioned in behind the two strikers.
Four-man midfield has brought better results under Lopetegui
So far, Lopetegui has used the system from the start in just four of his 13 games in charge of Madrid - often preferring to field Gareth Bale, Karim Benzema and Marco Asensio together up front in a 4-3-3 - despite the fact that he has achieved better results with four in the middle, winning three out of four matches. With a midfield trio, Madrid have triumphed in three out of nine games, and lost four times.
Buenos días! On today's front page ahead of tomorrow's #ElClasico: Lopetegui places his faith in Isco - the #RealMadrid coach is set to go with the Andalusian in a 4-4-2, with Bale and Benzema up tophttps://t.co/14JKKprS3W pic.twitter.com/Qzv7NOto1L— AS English (@English_AS) 27 October 2018
And playing with an extra forward hasn't made Madrid noticeably more effective in front of goal this term: thus far, they have scored an average of 1.50 a game (six in four) with four in midfield, and 1.55 (14 in nine) with three. At the other end, however, they do benefit from having more bodies in the engine room, having conceded 0.5 per match (two in four) with a midfield quartet, and 1.44 (13 in nine) with a three.
This doesn't appear to come down to control of possession, given that Madrid have in fact enjoyed a higher average percentage when using a 4-3-3 (66.6%) than a 4-4-2 (64.2%); rather, it seems to be the effect that the latter set-up has on the team's occupation of the spaces and its ability to offer cover in behind the full-backs - an area which has been a major Achilles' heel for Los Blancos this season.
Helped by the more solid presence enjoyed by the side when there are four in the midfield, Madrid have given the lie to the assumption that more forwards means more attacking presence: when in a 4-4-2, the European champions have had more shots per game (16 versus 15), of which more have been on target (7.25 against 6.7).
Roma display a clear example of benefits of 4-4-2
The prime example of the benefits of the midfield four is September's Champions League clash with Roma, in which such a system was used: Los Blancos ran out 3-0 victors, having had 26 attempts (sending 12 on target), boasted 60% possession and given their best display under Lopetegui - a level of performance which they have since tried, and so far absolutely failed, to replicate.