Real Madrid suffered a big setback on Tuesday, as the news broke that key midfielder Toni Kroos would be out for the rest of 2016 after fracturing a metatarsal in his right foot, per Marca.
With a maximum of a three-month layoff, dependent on surgery—yet to be decided whether required—manager Zinedine Zidane's most influential player this season will be a huge loss both technically and systematically for Real as they bid to continue an unbeaten run and improve their playing style at the same time.
The Germany international has been in good form this season, but Los Blancos need to find the right balance without him, which will not an easy feat considering injuries and lack of form elsewhere in the team.
The Good
Kroos and Zidane might be feeling down, but football is a constant revolving door of opportunities; when one player misses out through injury, the chance to play is there for someone else. And at a club as competitive as Real Madrid, each game in the starting XI is a big deal.
Thoughts will first turn to the man Kroos has been playing beside of late: Mateo Kovacic.
Zidane would have had a tough decision to make after the international break: continue with Kovacic in the side after an excellent run of form or move him out to make room for perhaps the team's most important player, Luka Modric, who returned to fitness with a cameo sub appearance against Leganes on Sunday.
Playing both together is the most likely scenario, whether continuing with a double pivot or a three-man midfield, dependent on Casemiro's fitness.
Before the Leganes match, the Brazilian hadn't started training with the ball after his own injury, but the international break has afforded the coaching staff time to get him involved once again, as Marca reported on Wednesday.
In principle, Casemiro behind a Croatian pairing of Modric and Kovacic covers all the bases: defensively sound, plenty of aggression, tactically balanced and, with the forward-thinking Europeans having the ability to surge forward, the ability to link with the attack and get into dangerous areas themselves.
But it's a long way from being a guarantee.
The Bad
Modric understandably looked a little rusty in his comeback appearance; he immediately got involved and was spraying passes around the pitch, but more than one was overhit. And although he looked to range forward in his usual manner, there wasn't the acceleration away from players you'd usually expect to see. It was clear he needs another game or two to hit top gear.
If that's the case for Modric, who missed seven games with injury, Casemiro's 11-match absence is only going to require a longer rehabilitation period once he's involved on the pitch again. His game is more demanding in terms of recovery runs, defensive aggression and quick, explosive changes of direction and pace.
Put into context, Modric and Casemiro have missed so much of the season so far that their combined game time in 2016/17 is 400 minutes under that of Kroos.
The returning duo aren't going to be firing on all cylinders immediately, and Zidane has to learn the lessons of his forward line this season. Cristiano Ronaldo and Karim Benzema were both lacking form and fitness. And thrown in together, they gave Madrid a lopsided and at times ineffective and frustrating attacking line.
Given the upcoming opposition for Real Madrid, local rivals Atletico Madrid, Zidane cannot afford for the same to happen in midfield.
If it's one or the other for a period, Isco is likely to reprise his role as the team's link player, drifting between midfield and forward lines, supposedly to create chances and offer more balance. But in truth, his languid style simply isn't hitting the right notes in a team that requires tempo and rhythm to improve its game.
Having started the last five matches in La Liga in succession, the Spaniard has recorded two goals (both against Betis) and two assists (against Athletic Club and Leganes). Yet his overall game has far from impressed.
Again, that's partly down to the dysfunctional forward line rather than Isco's inadequacies, and certainly his best performances in some months have been seen after this run of games, but he alone cannot make the difference.
The Worrying
Picking the starting XI is only half of Zidane's problem without Kroos.
There's a whole lot more to do to replace what the German has brought to the team this season and then even more to stop Madrid's upcoming opponents and help Los Blancos to continue sitting atop La Liga's standings.
In league play this season, per WhoScored.com, Kroos leads the team in assists, key passes per game, average passes per game, accurate long balls per game and pass success rate among players with more than three starts. He has been the Real's conduit from back to front in Modric's absence. And earlier in the season, when Casemiro was fit, he was a driving force in the left channel as one of the two more advanced central midfielders in the team.
Whether sitting centrally or pushing on, Kroos was in form and vital to forming the attack.
That remit will fall elsewhere, and Madrid must also be concerned with improving a defence that has leaked goals and made mistakes with incredible regularity this season—and against the toughest run of opponents of the season.
Ahead of the winter break and without Kroos, they face Atletico Madrid, Barcelona, Borussia Dortmund and Valencia, among other matches. The team's next five away games are against Atleti, Sporting CP, Barca, Valencia and the in-form Sevilla. If Kroos does not play in any of those games, Madrid will find it extremely difficult to control the centre of the park.
It has to be a one-game-at-a-time approach for Zidane and Co, and the derby at the Vicente Calderon is of the utmost important, even with a six-point lead over their rivals.
Madrid have habitually done well when they dominate play against Atletico and eventually find a way through the massed ranks at the back. But when allowing Los Rojiblancos to pressure high, force Real backward and dominate midfield, Diego Simeone's team that has emerged triumphant. Kroos is the most important piece of the chessboard to control space and time in possession, and Modric will be relied upon even more as a result—fully fit or not.
It's a tough period of games for Madrid in any case, but Kroos' injury makes it all the more keenly felt. Zidane cannot allow the German's absence to be an excuse for the wheels to fall off Real Madrid's season.