United’s Dwayne De Rosario, right, dribbles the ball in front of San Jose’s Nana Attakora during the second half of D.C.’s 2-0 road victory on Saturday. De Rosario scored two goals and was named MLS Player of the Week. (Thearon W. Henderson/Getty Images)

D.C. United Coach Ben Olsen was searching for shade after Tuesday’s practice at sun-splashed RFK Stadium when he turned to see Dwayne De Rosario lingering on the field to volley with teammate Stephen King.

“Hey Dwayne, get inside, you’re too old to be out in the sun!” Olsen hollered, drawing chuckles.

Ultraviolet rays might be Olsen’s only concern pertaining to De Rosario, 33, whose arrival five weeks ago from New York has transformed United’s attack. His two-goal effort in a 10-minute span of the second half Saturday produced a 2-0 victory over the San Jose Earthquakes, extending the club’s unbeaten streak on the road to six matches.

United (6-6-8) is one point shy of an MLS playoff berth and has played fewer games than all but four of the other 17 teams.

De Rosario “was in a big pool in New York with a lot of big players and I don’t think he was allowed to do the things he’s capable of doing,” captain Josh Wolff said. “So far for us, he’s been fantastic.”

With Wolff (hamstring) and Charlie Davies (knee) ailing, De Rosario moved up to withdrawn forward from attacking midfield Saturday. In a more menacing position, he broke the deadlock in the 57th minute, collecting Andy Najar’s long ball and taking advantage of defender Nana Attakora’s fall to sting a rising 22-yarder past goalkeeper Jon Busch.

Ten minutes later, he worked a fine combination with Chris Pontius, curling into the penalty area to receive a cross and drive it into the far side. The sequence unfolded so quickly, TV replays failed to vividly show how De Rosario struck the ball.

“It was a good ball; all I had to do was direct it,” he said of the right-footed stab in tight space, his third goal in five D.C. appearances. “Those are the ones when, if you catch it a little bit wrong, it will go over the bar.”

With Wolff and Davies under consideration for this Saturday’s match against Toronto FC (3-11-10) at RFK Stadium, Olsen will probably resist the temptation of leaving De Rosario — named MLS player of the week for his efforts against San Jose — on the frontline with rookie Blake Brettschneider and return the 11-year veteran to midfield.

“I’ve seen it since I came into this league and we expect that of him,” Olsen said of De Rosario’s scoring prowess. “That is what he’s about and he has helped us in a big way.”

McTavish, Quaranta return

Defender Devon McTavish and midfielder Santino Quaranta, who were among six players afflicted with a concussion this season, returned to practice Tuesday after missing six months and two-plus months, respectively. No timetable is set for their return to competitive play.

“I almost forgot what it felt like,” McTavish said. “I’m just happy not to be sitting in my apartment with the blinds down in a dark room. It’s good for my mental health to be back with the team.”

Said Quaranta, “I’ve never experienced anything like it with any injury and I have a whole new appreciation for what it does to your daily life.” . . .

Forward Joseph Ngwenya, who suffered a concussion in practice last week, is running again and should be available soon. Defender Brandon Barklage has been practicing after a multi-week layoff caused by his own head injury. . . .

Midfielder Kurt Morsink aggravated an ankle injury last weekend and was relegated to light running, while defender Brandon McDonald didn’t practice in order to recover from wear and tear. . . .

Wolff said of his injury, “It wasn’t a tear, it wasn’t a pull, it was just a little nuisance.”

A cure for home woes?

The combined record of United’s next three opponents (Toronto, Vancouver and Chicago) is 7-28-31. The Canadian clubs are a combined 0-15-9 on the road, but United is just 2-3-5 in Washington and 0-4-4 in the last eight home matches in all competitions.

“There seems to be a real collective effort when we go away,” Olsen said. “Hopefully that can translate into this weekend, and I’m confident it will.”