HARRISBURG, PA. – Washington Nationals officials had one goal for Stephen Strasburg in his initial minor-league rehabilitation outing Wednesday: Get through it in good health. Pitching for the Class AA Harrisburg Senators, Strasburg achieved that, allowing one earned run on four hits with six strikeouts and no walks in five innings of work against Richmond, the Class AA affiliate of the San Francisco Giants.

Strasburg, on the major league 15-day disabled list with what the Nationals have labeled a left trapezius strain, threw all his pitches and looked comfortable throughout the outing, which came under sunny skies at Metro Bank Park. He threw 71 pitches, 48 for strikes, and started 16 of the 20 batters he faced with a strike.

The Nationals, who open a homestand Wednesday night against Tampa Bay, will determine Strasburg’s next minor-league outing after they assess him physically back in Washington. Both Doug Harris, an assistant general manager, and vice president of player personnel Bob Boone watched the outing from behind the plate.

Strasburg’s 2015 season has been the rockiest of his career. In 10 starts, he has completed seven innings just once, failed to make it out of the fourth four times and has a 6.55 ERA with 1.721 walks-and-hits allowed per inning. He suffered a sprained ankle in spring training, and some Nationals officials are convinced altered mechanics to compensate for that injury have led to Strasburg’s poor performance.

Strasburg began his first start – and his first time in competition since May 28, when he walked off the mound in the second inning in Cincinnati – with the organizational goal to have him throw around 80 pitches, perhaps getting through five innings. He looked loose and threw easily in the first inning, retiring three batters on just eight pitches – all fastballs, seven of them strikes – to get a fly ball and two groundouts.

He set down the side in order in the second, finishing Richmond first baseman Ricky Oropesa with a called third strike and then getting third baseman Mitch Delfino to swing through a breaking ball for his first two strikeouts.

With one out in the third, Strasburg allowed his first base runner, a groundball single through the left side by catcher Jackson Williams. After a failed bunt attempt by opposing pitcher Adalberto Mejia – Strasburg threw out Williams at second – Kelby Tomlinson sent a 1-0 Strasburg offering to the gap in right-center. The ball – one Nationals center fielder Denard Span likely would have tracked down — glanced off the glove of Harrisburg center fielder Derrick Robinson and went for a run-scoring triple.

The other run he allowed came in the fourth after third baseman Matt Skole’s errant throw allowed a runner to reach base with one out. Groundball singles from Oropesa and Delfino followed to score the unearned run, but Strasburg struck out Williams with two on to end the frame.

The Senators pinch hit for Strasburg in the bottom of the fifth, and he departed trailing, 2-1.