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Not an awful lot went right for Liverpool in the summer of 2010.

Rafa Benitez, a European Cup-winning manager, was let go after a disappointing season. Roy Hodgson was somehow deemed the right man to replace him. Boardroom wrangles were ever-increasing amidst the hope of a sale, the threat of administration and the tyranny and ineptitude of owners Tom Hicks and George Gillett.

And the transfer window as a whole was, undeniably, a farce.

Out went squad stalwarts like Yossi Benayoun, Albert Riera, Fabio Aurelio. A clutch of youngsters and a reserve or two.

In came the likes of Paul Konchesky, Joe Cole, Danny Wilson, Christian Poulsen. Aurelio back in again. Of the nine who came in during that transfer window, only Brad Jones and Jonjo Shelvey remain at the club, plus Wilson who is out on loan and due to leave on a free transfer in the summer.

In no way, shape or form did Liverpool replace the quality who left with the same coming in, in pretty much any position, but there was one area of the field which suffered more than most and which Liverpool have failed to replace since that summer: the position of defensive midfield, and the player of Javier Mascherano.

The base of the Reds' midfield, the platform from which the likes of Xabi Alonso, Lucas Leiva, Steven Gerrard and Momo Sissoko had been allowed to go and play, creating or destroying, whatever their game was.

For a time there, Liverpool actually did have the best midfield in the world. Before the days, with all due respect, of Charlie Adam and Jay Spearing acting as the central pivot.

Three of that particular midfield quartet now play at Real Madrid, Barcelona and Fiorentina (on loan from PSG). Adam is now at Stoke, Spearing on loan at Bolton.

With El Jefecito in place, everybody could push further up the field, safe in the knowledge that behind them, when the ball was lost, was a terrier bulldog of a midfielder, snapping at the oppositions' attackers, covering 30 metres of turf like a madman and crunching into challenges with gusto.

In short, the defence had a Mascherano-shaped layer of fierce protection in front of it, and the team as a whole benefited.

When the Argentine midfielder walked out on the club that summer, understandably wanting to join Barcelona—though the circumstances of his exit left a rather sour taste in the end—Liverpool almost didn't have time to find his replacement.

Or, possibly, Hodgson thought Poulsen was up to the task.

Lucas Leiva, already a regular in a central role by then as the starter of plenty of the Reds' moves from deep, was asked to switch roles slightly again. Was asked to become not just the controlling midfielder of the ball, but also the one who won the ball back, shepherded attackers away from danger and patrolled the area in front of the defence with authority and force.

The Brazilian had gone from being a forward-thinking box to box midfielder upon his arrival on Merseyside, to being an enforcer-type defensive midfielder. Three years later, he is still the only senior player on the club's books who is tasked with that type of approach in the game, despite having missed the best part of a year with two long-term injuries.

Lucas has his abilities, no doubting it and no use denying it.

As a deep midfielder he can control games, he reads play relatively well to make interceptions and he is not afraid of putting the boot in, even when it might be wiser to resist at times.

On the other hand, he is lacking in great acceleration, is not the most imposing of presences and, oddly, suffers either lapses in concentration or else in concluding what the best course of action should be: allow an opponent to run through unchecked, or commit the foul and take the card—but prevent a chance to score?

Liverpool have ranged from good to woeful this season in doing a job of protecting their back four. While the central defenders themselves—and the full-backs—have gone through spells of extreme indifferent form, they can hardly be expected to do the best job if the midfield offers too little protection.

That is what has befallen the Reds this season on too many occasions.

Steven Gerrard and Lucas, as a partnership, has not been a hugely capable one when not aided by the work-rate and consistency of a rejuvenated Jordan Henderson

What the Reds are missing, really missing at times, is a player who can stop attacks from their opponents before they have even largely begun. Not just someone to make a tackle in the centre of the park—though that has at times been an issue too—but someone to guide an opponent away from goal.

A strong defensive midfield presence to threaten to clear out the ball, the man and the first six rows of the stand, if necessary.

On no less than seven occasions this season, in league play alone, Liverpool have directly conceded a goal as a result of teams playing or running, unchecked, straight through the central midfield area which the holding player should be occupying in front of the defence.

On many more occasions, such play has led to set pieces or shots on goal being attained.

Mascherano wasn't the biggest in physical stature, but very, very few attackers, whether skilful or strong, fast or clever, managed to get the better of him.

Liverpool certainly will need to look at adding a centre-back or two in summer, and the manager may well have his eyes on further attacking reinforcements as well, but it would be a grave mistake for the club to think they can significantly progress further without finally addressing the issue of, at last, replacing Javier Mascherano for a seventh consecutive transfer window.

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