For the first four games that Brendan Rodgers attempted to play Steven Gerrard as Liverpool's deepest midfielder, he was sent out to do the job almost exactly as Lucas would. He was given freedom as a holding player, and that freedom both with and without the ball got him into trouble whenever his natural attacking instincts kicked in. Against Oldham and Bournemouth in the FA Cup and Stoke and Aston Villa in the league, the Steven Gerrard experiment was a soul crushing failure.
Whether it would have continued had Lucas remained fit or whether the Brazilian's injury forced Rodgers' hand may be an open question, but given Liverpool's dwindling midfield options, in the end Rodgers didn't have much of a choice but to continue playing Gerrard as the midfield's deepest, holding player. Fortunately for him, of late things haven't gone nearly as poorly as they did in those the four matches, and Rodgers deserves credit for the tactical tweaks that have improved the side.
Bringing three back into midfield at the expense of two up front has been the main shift after Rodgers' dalliance with two in the middle, and against Everton and Arsenal in particular there appeared a realisation that he can either run with two strikers sat up top or he can have Gerrard as his deepest midfielder—he cannot have both. Nervous Liverpool fans, though, will point to the stumble against West Brom between the Everton and Arsenal matches as a lingering cause for concern.
Gerrard as the holding player worked against Everton and Arsenal in part because whichever of Daniel Sturridge or Luis Suarez ended up on the wing, Liverpool's out of position strikers were generally impressive in the new roles they were asked to play. Against West Bromwich Albion, a side most expected Liverpool to beat handily, their workrate when on the wing dropped off just enough to unbalance Liverpool's midfield, often drawing either Gerrard or Jordan Henderson outside to cover.
Against Everton and Arsenal, moving Philippe Coutinho inside to play as a box-to-box midfielder also worked wonders, and the playmaker tracked back diligently to maintain Liverpool's numbers in the middle. With less room to counter into against West Brom, and though Coutinho stuck to his task without the ball, he appeared far less effective. Coutinho has often talked of thriving on the space that can be found by beating the first defender in England; against a side that sat back that space disappeared.
Gerrard as the holding player worked against Everton and Arsenal in large part because of the players around him. It worked because Coutinho's presence gave Liverpool numbers in the middle and saw an effective attacking outlet sat immediately in front of Gerrard. It also worked because whichever of two the strikers ended up on the wing tracked back diligently—or at least tracked back mostly diligently—allowing the three midfielders to stay compact when Liverpool didn't have the ball.
More than that, it worked because against two clubs most would consider top competition, Gerrard stuck to his task and kept the play ticking over. The players around him limited his tendency to roam without the ball, while with it Gerrard himself limited his tendency to employ the kind of Hollywood balls that in those first four matches in the deep role had led to possession being turned over far too easily, handing it to the opposition in dangerous areas and with Liverpool's fullbacks pushed on.
Against West Brom, there were fewer players around him when Liverpool didn't have the ball and his defensive responsibilities increased. Against West Brom, with Coutinho lacking the kind of space he thrives on countering into, Gerrard began to hunt for the killer pass rather than prioritising possession. Gerrard and Rodgers both deserve credit for finding a way to make the experiment work against two of Liverpool's biggest opponents. Now they need to find a way to make it work against a side at the bottom of the table.
It seems as though it should be so simple. After all, if Gerrard can take on the holding role to some success against Everton and Arsenal, then surely he can take it on against Fulham. So far, though, that hasn't been the case. So far, keeping Gerrard's natural instincts in check when there's less support around him and the match seems as though it should be an easier one has turned out to be about as far as one can get from simple.