Injuries, a snowstorm, schedule changes, suspensions – D.C. United faced it all in the 2012 Major League Soccer (MLS) Cup playoffs. In the end, United eliminated the arch-rival New York Red Bulls in the Eastern Conference semifinals, but fell to the Houston Dynamo, 4-2 on aggregate, one step short of hosting the MLS Cup final.

For a club that has won four MLS Cups, but none since 2004, that taste of glory is the starting point for a 2013 season in which much may be expected, but many questions remain. United got an early shot against its playoff nemesis from last year, Houston, in Saturday night’s season opener. But D.C. fell, 2-0. United failed to put a shot on goal (statistically anyway, Chris Pontius hit the crossbar with a free kick).

Part of the offensive struggle can be attributed to the suspension of star midfielder Dwayne De Rosario. The Canadian international (who missed time due to a knee injury last season suffered while playing for Canada) was suspended two games by MLS just before the season opener for an incident in a preseason match against the Philadelphia Union. De Rosario, the 2011 MLS Most Valuable Player, is eligible to return to action March 16 when United visits the Red Bulls – the team that traded De Rosario to United in 2011.

De Rosario’s creativity and offense was certainly missed Saturday night, but the loss also served as a lesson that United must be potent throughout the lineup rather than relying on one player. Gone from last year’s attacking corps are Branko Boskovic and Hamdi Salihi, as well as Andy Najar, who had developed as a promising outside defender to complement his offensive skills. Najar was sold to Belgian club Anderlecht prior to the 2013 season.

But with a focus on who is still here, let’s take a quick position-by-position look at D.C. United in 2013.

FORWARD: Lionard Pajoy, acquired from Philadelphia during the 2012 season (for Danny Cruz, the victim of De Rosario’s alleged preseason headbutt), started alone at forward Saturday, but United didn’t get enough ball possession to get Pajoy into the game. If Pajoy was on the ball in the attacking zone, he usually didn’t get enough support from teammates to make a play. New United midfielder John Thorrington joined Pontius and DeLeon in the attacking midfield, but as is typical in early-season game, the links between midfielders and the lone forward either weren’t there, or decisions weren’t made fast enough to take advantage of numerical edges in the attack. Having De Rosario back will certainly help that.

Newly-acquired Carlos Ruiz, long a thorn in the side of United and its fans, didn’t get off the subs’ bench Saturday after not playing in MLS in 2012. Ruiz, a Guatemalan international, has played for four other MLS clubs previously, scoring 88 goals and winning the MVP award in 2002. Now 33, Ruiz will need to score goals for United to succeed, and for the fans to potentially soften their opinion of the acquisition.

Casey Townsend, 23, is the only other forward listed on United’s roster over the age of 20. He was acquired in an offseason trade with Chivas USA.

MIDFIELD: The engine room will be run by De Rosario upon his return, but he should have plenty of help. A healthy Pontius, who can play up front as needed, is vital for United. Pontius is dangerous taking free kicks, can work on the ball in traffic to find space for shots/passes, and has an excellent shot. Perry Kitchen’s performance as a defensive midfielder will be critical, and development should be expected after starting 62 league matches the past two seasons. Veteran Marcelo Saragosa, 31, will be counted on for depth and played 83 minutes as a starter in the loss at Houston, as head coach Ben Olsen employed a 4-5-1 formation.

Out wide, Nick DeLeon will try to improve on a tremendous rookie season. DeLeon scored 6 goals in the regular season, then netted a memorable late goal (one of two playoff strikes) at Red Bull Arena to give United a 1-0 win at New York that allowed D.C. to advance to the Eastern Conference semifinals.

Englishman Lewis Neal, 31, provided valuable minutes last season as a reserve, though he was not available for selection Saturday night.

DEFENSE: The quartet of Dejan Jakovic, Brandon McDonald, Chris Korb, and Daniel Woolard started in the back Saturday night, though Woolard lasted only 45 minutes before being replaced by James Riley. All four starters are aged 25-28, and could be regarded as in their prime. Jakovic has received call-ups (with De Rosario) to the Canadian National Team. Robbie Russell, 33, is the veteran of United’s backline.

Perhaps the biggest issue facing the defense is consistency. If United can keep a regular starting lineup such that communication and positioning improves through players being used to working off each other, the defense can improve. United conceded 43 goals last season, tied with San Jose for third-most among 2012 playoff clubs. With forward depth being less than last year, United must reduce the goals conceded to remain a playoff contender in 2013.

GOALKEEPER: Speaking of stopping goals, United will rely on 22-year-old starter Bill Hamid. Hamid, who started Saturday’s loss at Houston, is a talented shot-stopper, who now must perfect the arts of distribution, organizing defenders, and controlling his area to continue improving. Hamid won 13 games last season with eight shutouts. He also picked up his first bit of international experience with the United States National Team in the MLS offseason.

Backup goalkeeper Joe Willis earned notoriety last year for his performance in the second game of the Eastern Conference semifinal at New York. Called in cold after Hamid was sent off, Willis stopped Kenny Cooper’s penalty kick to leave the match scoreless until DeLeon scored the goal that allowed United to advance to the Eastern Conference final. Willis, 24, was 4-4-3 last season in goal for United.

LOOKING AHEAD: At first glance, repeating last year’s 53-goal haul is a longshot for United. De Rosario and Pontius must stay healthy all season. That said the team defense must improve for United to again contend and be around late in the playoffs.

Replicating last season’s 58 points (17-10-7) is a tough ask, and it took 53 to make the playoffs out of the East last season. Saturday’s loss aside, the East isn’t so deep that United shouldn’t expect to compete.  Remember, United haven’t lost a league match (including playoffs) at RFK Stadium since last season’s home opener vs. Sporting Kansas City. United is 12-0-6 in 18 matches since that defeat on March 10, 2012. Similar home dominance this season would keep D.C. in the race.

We’ll know more about this group’s ability away from home once De Rosario returns and Ruiz is fit for selection, when the team has its creativity back and Olsen has the freedom to craft a more threatening attacking lineup.

Follow Ed Morgans on Twitter:  @edmorgans