When pondering how Manchester United might cope with Phil Jones' likely absence for the return UEFA Champions League knock-out tie leg with Real Madrid, the concern is basically how can Sir Alex Ferguson's side find an alternative way to contain Cristiano Ronaldo?

Just to briefly recap, Jones has been instrumental since the new year -- from a right-sided central-midfield position -- in helping to contain influential attackers such as Tottenham's Gareth Bale, Everton's Marouane Fellaini, and Madrid's Cristiano Ronaldo. This hasn't necessarily been in strict man-marking roles as some have suggested -- although, his tracking of the Belgian was pretty much a shadowing job -- but rather it's been in an inside cover role. Whenever Bale or Ronaldo drifted into central areas or even to the opposite flank, the energetic Jones would eagerly follow them around the pitch in an effort to shackle them. In that regard, I suppose there's remnants of man-marking.

United don't have a like-for-like replacement for Jones. The versatile 20-year-old fancies himself as a defender -- specifically as a central one -- but his combativeness, mobility, and energy provides Ferguson a defensive presence in central-midfield that no other player in the squad can. If Jones is indeed unavailable for Tuesday night's European tie, the manager will have to find a different way to cope with Ronaldo -- arguably the most dangerous attacker in the world at the moment.

The most obvious candidate to replace Jones in midfield is Tom Cleverley. The England international has generally been first-choice alongside Michael Carrick for most of this season's key encounters. However, against Madrid at the Bernabeu, the midfielder was never involved. If he does get the nod for return leg against Jose Mourinho's side, it's most likely going to be in a double-pivot with Carrick. And despite Cleverley's qualities -- technical abilities which Jones does not possess -- he cannot provide the same sort of shielding qualities that the combative 20-year-old can.

The most typical system for United in big games this season has been a counterattacking 4-4-1-1. Early on in the season -- particularly away to Chelsea, home to Arsenal, and away to Manchester City -- this meant keeping the lines compact, absorbing pressure, and then springing forward on the counterattack when possession was won. More specifically, the breaks often occurred on the flanks.

Diagram 1: United often created 2 v 1 overloads down the flanks with the full-back and winger combining after lightning quick breaks.

This is a system that certainly is very possible for Ferguson's side against Madrid. Rather than having a particular central-midfielder like Jones shadow Ronaldo whenever he inevitably cuts inside towards goal from the left, an organized and compact shape would require a cohesive effort in order to shackle to the Portuguese attacker. Madrid's other wide attacker -- Angel di Maria -- also tends to move into increasingly central positions the nearer to goal he gets. In this counterattacking 4-4-1-1 system, United would simply hope to absorb and deal with the pressure as a collective unit whenever the Madrid front four funnel towards the United goal.

If Cleverley -- or possibly Ryan Giggs or Anderson -- is selected in a double-pivot alongside Carrick, then the other critical selection choice with Ronaldo in mind is the right-winger to partner right-back Rafael. During the reverse fixture at the Bernabeu, Wayne Rooney was tasked with a right-sided attacking role. However, the Englishman ended up having a poor match, especially from a defensive perspective. Early on in Madrid, Rafael was seen yelling at Rooney because he needed more protection and it was Mourinho's left-back -- Fabio Coentrao -- that would've opened the scoring if not for a brilliant David de Gea save tipped onto the far-post. After Danny Welbeck did score an opening goal for United against the run of play, Rooney was immediately seen darting to the coaching staff near the touchline with his arms spread wide. Basically, he was expressing his concern that he and Rafael were not compact enough. Quite simply, there was little cohesion between Rafael and Rooney and that right-sided partnership is not likely to be repeated.

Much of Rooney's and Rafael's defensive struggles at the Bernabeu -- particularly in the first-half -- was masked by Jones performing well in his inside cover role. If Jones is out as expected for Tuesday night's game, then that same sort of protection won't be available and there will more of an onus on the right-sided attacker to help Rafael deal with Ronaldo and Coentrao. The most likely candidates appear to be Nani and Antonio Valencia.

In general, United's wingers have been disappointing this season. This is presumably why Ferguson elected to choose Rooney -- more naturally a central-attacking player -- rather than one of his struggling wingers. The main right-side options, though, Nani and Valencia, have shown improved form since the tie in Madrid nearly three weeks ago. The Portuguese winger, in particular, has shown flashes of his match-winning abilities and he's without a doubt the best attacking option for that flank at the moment. The Ecudorian winger still isn't convincing in attack, but he's in contention to start because of his defensive abilities out wide.

Nani's defensive ability has improved over the years and he's typically adequate now, despite having the frustrating tendency to switch off in moments. If Jones were fit to feature in central-midfield, then the Portuguese international would probably be the best option to feature on the right. Without that sort of shielding available in the center of the park though, Ferguson will be contemplating if Nani can offer adequate protection for Rafael.

Valencia has a wonderful understanding with Rafael and this is undoubtedly the most balanced partnership on the right side when the winger is in good form. The problem, though, is that he's not in good attacking form. Ferguson's worry with Valencia will be wondering if the winger can provide enough thrust and ability in attack when United break forward. If there's no effective outlet on the right-side, then the Reds will continually be re-absorbing attack after attack from Madrid. These are the sort of dilemmas the gaffer is likely considering with the possibility of Jones being out.

If Ferguson still doesn't trust either Nani or Valencia to start the match, then other possibilities on the right include Ashley Young, Shinji Kagawa, Cleverley, Welbeck, or Rooney (again). None of these players, except for Young, would provide genuine width so there would be concern if one of these players -- in a nominal wide role -- would be able to provide an outlet down the flank in order to relieve pressure. Against Madrid with Rooney on the right, and against Spurs recently with Cleverley on the right, United looked disjointed when possession was won because they didn't have their familiar out-ball near the right touchline. Because of this, in both those matches at the Bernabeu and at White Hart Lane, United were forced to deal with attack after attack because they had little sustained relief from their own attackers.

There's always the possibility, of course, that Ferguson could go away from his familiar 4-4-1-1ish shape and instead, use a diamond midfield or a 4-3-3/4-5-1. The diamond is a system that United have used numerous times earlier in the season while a three-man central-midfield has been something deployed often by Ferguson in past years for difficult European ties. Both shapes would allow the home side on Tuesday night to clog the midfield and perhaps better deal with the onrush of attackers through the middle -- Ronaldo, di Maria, Gonzalo Higuain or Karim Benzema, Mesut Ozil, and Sami Khedira -- whenever Madrid near the United goal.

United are arguably a team hitting peak form right now for this season and they did tremendously well to earn a 1-1 away result at the Bernabeu. Tuesday night's game, though, is obviously a challenge against one of Europe's best sides and against perhaps the world's greatest attacker at the moment in Cristiano Ronaldo*. There is no shame if Ferguson takes a reactive approach and besides, Madrid aren't a team you want to recklessly attack and then leave space for them to counterattack into -- they are perhaps the best side in the world in quick transitions.

* Lionel Messi's relative dip in form is likely to be extremely temporary.

Jones' likely unavailability against Ronaldo and co. presents Ferguson many worries. The pseudo man-marking ability by the versatile 20-year-old has been an extraordinary asset in recent months and now because the value of it is very obvious, particularly against Madrid, the absence of that option at the manager's disposal is likely to give him headaches while planning for Tuesday night. It's likely going make selection-choices more complicated than usual because of the trickle-down effect of Jones' absence. There will be an emphasis on the collective rather the reliance of the Englishman's individual defensive abilities.

This could make United a more balanced side though. Without having one central player being so concerned with one player from the opposition side, there would be more stability in the overall shape. Carrick would presumably not be so isolated against the likes of Ozil, Khedira, and Xabi Alonso while Patrice Evra would have a bit more assistance in dealing with di Maria. But then again -- the original problem -- would Jones not shackling Ronaldo allow the ruthless Portuguese attacker too much freedom? It's uncertain how United will perform if Phil Jones doesn't feature on Tuesday night, but it will make them a very different team.