WASHINGTON -- D.C. United finally returned home on Sunday from a week-long road trip to Seattle and Colorado, and the squad can now enjoy a three-day break with no training sessions until Thursday ahead of an idle weekend in league play. Based on Saturday's 3-0 loss to the Rapids, it's a much-needed rest, especially for a back line that has allowed seven goals in its last three matches."I'll have to take some time to think about that," said head coach Tom Soehn when asked if the defeat at Dick's Sporting Goods Park offered any silver linings. "It's pretty disappointing, but our guys deserve a little rest now and we can't dwell on this."United's western expedition exposed some vulnerabilities in the defensive sphere. But with the halfway point of D.C.'s season close at hand, it's worth noting just how much has changed on East Capitol Street since the dark days of 2008.Last year United surrendered 51 goals in league action (an average of 1.7 per game) and allowed another 17 goals in 10 CONCACAF international matches in a bitterly disappointing campaign. Now United sits in first place in the Eastern Conference, having whittled their goals-against average down to 1.5 per game -- a number recently swollen by their just-completed road trip -- despite reverting to a forward-leaning 3-5-2 formation and introducing several newcomers in major roles.Few occupy a more pivotal place than Dejan Jakovic, the young center back who arrived in Washington as one of United's last preseason signings but has rapidly established his importance to the United cause. In fact, the 23-year-old Canadian's defensive displays are looking like a crucial building block for his team's '09 aspirations and could help vault him forward in the international arena as well.After occupying the bench at Serbian club Red Star Belgrade for months, Jakovic had to learn an entirely new system in his first few weeks in D.C. when Soehn returned to the five-man midfield scheme originally introduced by former coach Peter Nowak. Though his physical and technical gifts were evident from his first moments in a Black-and-Red jersey, Jakovic was handed a laundry list of new tactical and psychological challenges, ensuring a few early fits and starts."It's tough. There's not a lot of teams that play three in the back," he acknowledged last week. "Even if you look overseas, no one really plays with three in the back. It's mostly to get control of the midfield -- we've got five guys in the middle so we can control the play. But it's been hard at times. There's a lot of one-on-one battles that you have to deal with."The central defender's role at D.C. United has been something of a poisoned chalice in recent years. Ever since Ryan Nelsen departed for the English Premier League after leading United to an MLS Cup title in 2004, the capital club has searched for backs with the steadiness and solidity to anchor what is traditionally an attacking-minded side.Bobby Boswell seemed to be the answer after he impressed as an unheralded rookie in 2005 but a perplexing loss of form led to a relocation to Houston, where he has since flourished with Dynamo. Last year D.C. turned to two veteran South Americans, Gonzalo Peralta and Gonzalo Martinez, with an eye towards international competition. After a strong start, the duo slipped well down the pecking order by season's end and soon returned south.Yet Jakovic has taken to his task with remarkable efficiency. His blend of size, speed and skill has keyed United's restoration of the 3-5-2 shape that allows more of the club's attacking talents to see the field. His comfort on the ball -- Soehn speaks approvingly of the Croatia-born Jakovic's "calmness" -- has helped D.C. transition out of defense with added fluidity."His play's been pretty stellar," said Soehn last month. "I think we're real happy with his progress."Of course, the coaching staff had to address weak points even as they delighted in Jakovic's rapid adjustment. First and foremost, Soehn refused to allow the 23-year-old's quiet nature to inhibit his verbal marshalling of the back line."Right away, as soon as I came into preseason, Tommy was all on me about screaming, telling players where to go and stuff," recalled Jakovic with a sheepish grin. "I think I've gotten a lot better with that. I'm still working on it but I think it'll come."Expectations remain high amid what is essentially on-the-job training, and now Jakovic will face a new test: juggling club and international duties. He won his first senior cap last year and Canadian national team coach Stephen Hart, taking note of Jakovic's progress in D.C., has included him in his squad for this summer's CONCACAF Gold Cup, which will involve missing at least three United matches."I'm looking forward to that," said Jakovic, who is cautiously optimistic about his prospects for playing time against some of the region's top players. "[Hart] said I've been doing well and really wants me to come in. I was happy to hear from him and glad I can represent Canada, my country."Charles Boehm is a contributor to MLSnet.com.