De Rosario's introduction – even in a limited capacity – offered United hope that it can overturn its two-goal deficit to Houston and seal a berth in MLS Cup.

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Imagine the roar of the RFK Stadium crowd if Dwayne De Rosario digs as deep as he can and steps up to the halfway line in the second half on Sunday afternoon.Such a scenario appeared fanciful at best when De Rosario suffered a left MCL sprain in September. Few observers expected United to thrive in his absence (6-1-3) or De Rosario to recover in time to play before the end of the season.It looks far more plausible now with the reigning MLS MVP back on the training field ahead of Sunday's Eastern Conference championship second leg affair against Houston. De Rosario isn't fully fit, but he could feature in a limited role if the circumstances require him to lend his services to the cause.“He’s a lot further along than we would have expected,” United assistant coach Chad Ashton told the Washington Post on Tuesday. “We are very optimistic he can play.”United might need De Rosario to help turn the tide after a 3-1 first leg defeat to Houston. The final result masked a decent road performance, but the resulting deficit leaves United with plenty of work ahead to rectify the situation.De Rosario's limitations actually help Olsen as he plots out a strategy to overtake the Dynamo. It isn't an easy task. There are already enough lineup uncertainties in play after the injuries suffered by Brandon McDonald (calf), Chris Pontius (groin) and Marcelo Saragosa (hamstring) in the first leg and with Andy Najar ruled out through suspension without throwing De Rosario into the starting mix. His inclusion from the start – helpful as it may be – would require certain accommodations that aren't on the table right now. Instead of trying to integrate De Rosario as a starter, Olsen can change the personnel and rely on the recent formula – keep it tight at the back and push forward at the right times.The two-goal hole may look significant now, but one goal alters the equation significantly. United – like Houston, though in different ways – is perfectly capable of grinding out a 2-0 home victory even when faced with defiant opposition. It can hold out against the potentially tempered Dynamo forays into the attacking half, barring any lapses in concentration or the unfortunate omission of McDonald. It can even create enough chances at some stage to score the pair of goals required to send this series into extra time. It doesn't matter when they are taken, per se, though earlier is certainly better from a confidence perspective. It just matters that they arrive at some point to make De Rosario's potential injection relevant.And the introduction of the former Dynamo star at some point during the second half looms as potentially significant. The same unique qualities that make integrating him back into this current United side somewhat difficult make him absolutely vital in chasing the game. He contributes ingenuity and work rate in the attacking third. He offers the quality in front of goal currently missing from Olsen's forward options. He provides the dollop of class and the touch of experience required to navigate the tricky terrain ahead in this decisive fixture.De Rosario's arrival supplies hope in a perilous situation. The current state of affairs does not necessarily indicate a conference championship exit beckons, but a tattered squad can only do so much even with the vociferous backing of the United supporters. The prospect of inserting a seasoned figure capable of altering the calculus if required bolsters United's chances of hosting the final on Dec. 1.For that reason and for so many others, those supporters will emit a roar loud enough to be heard throughout the District if and when De Rosario prepares to enter the match on Sunday. He may or may not save the season, but his arrival to aid the cause strengthens the belief that United will find some way to keep its dreams before the final whistle blows.