In a best-case scenario, Chelsea will have three fit senior players able to operate in midfield against Wolves on Monday evening. One of those will be the injury-plagued Romeo Lavia, who remains a flight risk at any moment.

Fortunately for Enzo Maresca, Moises Caicedo has proven himself capable of carrying the load, more often than not. However, when he is left with Enzo Fernandez, cracks have begun to appear in recent weeks.

Fernandez, while Chelsea's best and most creative progressor of play from deep, lacks the defensive know-how and ability to partner Caicedo effectively. It is why Maresca has turned to pushing him forward at every available opportunity, putting the two more physical and defensively sound bodies of Lavia and Caicedo together.

The issue is that Lavia has failed to remain fit once more for Chelsea and even with him back in the fold there are doubts over just how much of any given match he can complete. After near-enough an hour last week against Bournemouth he missed training along with a host of Chelsea teammates in the build-up to welcoming Wolves on Monday evening.

Fernandez was another who was absent for sessions at Cobham. Given that Rento Veiga is clearly not trusted in midfield and all of Cesare Casadei, Carney Chukwuemeka, and Kiernan Dewsbury-Hall are looking to leave the club this month, there is a chance Caicedo plays at Stamford Bridge as the only fit midfielder.

Sam Rak-Sakyi, who made his debut and impressed in the Conference League last month and has trained with the senior squad in the last few days before Wolves, is one alternative. He is a reported target for Chelsea legend Frank Lampard at Coventry City, though, and could yet depart before the February 3 deadline.

More pressingly, extending beyond just the next Premier League meeting, Maresca has an issue. He is not only working with fitness-battling and heavily fatigued options in the middle of the park, but any chance of rotation with those on the fringes is being impacted by January transfer window expectations. Chelsea themselves aren't readily looking at alternatives or reinforcements currently.

Kobbie Mainoo is a name they admire, but do not see as likely this month. He is pretty much the only real No.6 linked even vaguely closely with a move.

What Chelsea do have, instead, is the option to recall one of their out-on-loan midfielders. Both Lesley Ugochukwu and Andrey Santos fit the profile missing at Chelsea both for depth and also starting quality.

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Ugochukwu, currently at Southampton, had a frustrating first six months on the south coast - going through what Santos did at Nottingham Forest 12 months ago. He is in the plans of new manager Ivan Juric, though, and has now started to play more often in the past couple of weeks.

As for Santos, he is excelling at RC Strasbourg in his second loan at the BlueCo-owned Ligue 1 outfit. He spent the second half of last season there under Patrick Vieira - and helped to avoid what would have been an embarrassing relegation.

Now playing for Liam Rosenior, Santos has continued his form regardless of a rocky patch for his team. He is having one of the best loan seasons for any player across Europe.

The Brazilian youngster is valued immensely by Chelsea and has, on paper, the game to offer plenty to Maresca right now. He could act as competition or simply back-up for a trio of midfielders being pushed to their limit physiologically.

With Santos and Ugochukwu both in a position to make an immediate impact for Chelsea, if required, the recall options are essentially a get-out-of-jail-free card after Maresca settled so quickly on his preferred players and those who he didn't even fancy for a fringe squad road. It was the same method Chelsea used at centre-back.

Aiming to cope with injury issues for Wesley Fofana (the Lavia of defence) and Benoit Badiashile - as well as Axel Disasi playing the unwanted and set to leave in January role for the backline as well - Chelsea chose not to dip into the market. Instead, with Trevoh Chalobah at Crystal Palace, Chelsea exercised their recall option and didn't spend a penny to add more depth.

The plan, it seems, is to pursue other targets in the summer. Saving money now, while learning more about the players already on the books rather than spending big, has been the cautious way forward.

Maresca, though, does not see Santos (in particular) coming back just yet. "Because at the moment we don't know if it's a problem for them [the in-doubt midfielders], just that for today they were out and we don't know if they will play the next game," he explained.

If any of the injuries prove to be long-term problems for Maresca, then the club may well have to re-evaluate their stance for Santos and Ugochukwu. The bad news is that it exposes squad-building flaws for what they are but, on the flip-side for Maresca and Chelsea, both players are available to add to his squad for free.