D.C. United finished last in the Eastern Conference last year, 18 points out of the playoffs. But it has been slightly more aggressive with its spending in recent months, highlighted first by the trade for 23-year-old Argentine Yamil Asad and now the signing of English legend Wayne Rooney to a 2 1/2-year guaranteed contract worth about $13 million.

Rooney, 32, is a household name and a year removed from 10 Premier League goals with Everton. There is no doubt that he has declined from his Manchester United prime, but he won’t stand around and be a liability, like Andrea Pirlo at New York City FC.

So, then, how will he fit with the current squad?

That simple question has stuck with the notoriously positionless Rooney throughout his career, especially as his aging has highlighted his lack of pace and pushed him back into the central midfield. It’s unlikely he will be trusted as a lone striker in D.C.’s attack, in part given the defensive and pressing responsibilities that position carries and also because of more favorable options.

Coach Ben Olsen’s current attacking system, set up in a 4-1-4-1 formation, is based on the interchanging of the second “4” line, with striker Darren Mattocks leading United’s press ahead of it. Luciano Acosta, charged with the creative duties of a number 10, has energetic box-to-box midfielder Paul Arriola (a converted winger) next to him, allowing the Argentine to drift across the front line. Asad and his opposite winger, Zoltan Stieber, help to flood the center of the pitch by inverting off their flanks.

This system, while it capitalizes on the natural athleticism and ground-covering abilities of the attackers, has two troubling disadvantages. It often leaves defensive midfielder Junior Moreno to fend for himself in front of the back line, a troubling predicament for any team. And given the lack of a true facilitator, United struggles to keep the ball in advantageous areas: D.C. has attempted just 87.9 passes per game in the attacking third this season, the third-fewest in MLS.

The benefits speak for themselves: When you have the ball closer to the opponent’s goal, you have more chances to get into scoring position, and you pin the opposition farther from your own goal. As energetic and occasionally prolific as D.C.’s attack has been this season, it struggles to produce enough quality to sustain attacking patterns and create consistent space for its talented attackers.

Therein lies the most significant benefit of having Rooney. Whatever athletic capability he has, he will provide a level of connectedness and nuance with the ball that United has not seen with this squad. Rooney is a skilled and smart passer, able to change the dynamics of a possession with one touch. Acosta is flashy, but he has not been able to do that.

Rooney’s presence may encourage Olsen to switch full-time to a 4-2-3-1 formation, which would put more numbers behind the ball but, paradoxically, also increase D.C.’s attacking strength. By having two dedicated midfielders in front of the defense, United would be able to control the middle of the field more effectively, allowing it to create space for possession.

With Rooney inserted into the central attacking position behind Mattocks, he would be free to roam, connecting D.C.’s attacking possession and putting himself in goal-scoring positions — historically his greatest strength. This is how it could look:

Acosta, theoretically, could be moved out wide to act as a secondary creator. Taking away the weight of being D.C.’s primary attacking distributor could be good for Acosta and would give him the ability to attack more freely. A number of MLS number 10s (notably Seattle’s Nicolas Lodeiro and FC Dallas’s Mauro Diaz) have thrived while creating from the flanks.

Arriola would have to become more dedicated to defensive work, and he would have to set himself up deeper in the formation to assure Rooney’s presence does not erode United’s defense. It would be an adjustment, but Olsen has 18-year-old natural box-to-box midfielder Chris Durkin waiting on the bench, ready to step in if needed.

The flaw of this look is width, or a lack thereof. Asad and Acosta would spend a considerable amount of time stepping into the middle of the field to find additional space, congesting that area and leaving the wide areas bare. United doesn’t have fullbacks who are able to overlap and fill that space; the team would have to complete a trade for a player such as Seattle’s Waylon Francis to solve this problem.

Nevertheless, this lineup could both maximize Rooney’s talents as a connector and goal-poacher and mask his deficiencies in mobility by moving closer to a double pivot midfield system. It is an upgrade over what United has now, even if it does not precisely subscribe to the vague ideals of Benny Ball.

It just might lift D.C. United into MLS’s modern era, too.

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