J Pat Carter/AP

Jayson Werth began his rehab assignment on Wednesday in Woodbridge, played three innings for Class A Potomac, went 1 for 2 at the plate and tested out his strained right hamstring in a game for the first time in over two weeks. He ran well on the bases without any apparent trouble in the first of two planned rehab games, still hoping to rejoin the Nationals on Saturday in San Diego.

“Pretty good,” he said following the game against the Wilmington Blue Rocks, a Kansas City Royals affiliate. “Been a couple weeks since I’ve been out there but a step in the right direction.”

Werth started in right field and hit second. He grounded out to second in his first at-bat, running smoothly down the first base line. In his second at-bat, he worked a full count and roped a single to center. He took second base easily on a wild pitch.

And on the subsequent ground ball, Werth was caught in a rundown between second and third. Billy Burns, who was on third base, took off for home on contact and was also caught in a rundown. Werth got to third base just as Burns raced back to it, but Burns then took off for home and somehow avoided a tag. Werth was the unlucky out in a play that felt like it could happen only in the minor leagues. He got almost half a game’s worth of running in that one rundown and left after his two at-bats for that reason.

“A fun day down here in Potomac,” said Werth afterward.

Werth hopes he will get at least three at-bats Thursday. Werth has been testing his hamstring even after he officially landed on the disabled list on May 11. He hasn’t played since May 2 in Atlanta. He participated in pre-game workouts on Tuesday in Potomac. Saturday would be the first day he is eligible to be reinstated from the 15-day disabled list.

“I’ve been kinda ramping up to this point,” he said. “Got on the field, which is good, and everything went well. We’ll see how it goes tomorrow. The decision is not mine so we’ll see what they say.”

Werth landed on the DL with lingering cramping. An MRI last week revealed he had a slight hamstring strain, a condition aggravated by dehydration attributed to a stomach bug. He was prescribed antibiotics for the stomach bug. The cramping, Werth said, has improved.

“I’ve been running and that’s the thing,” he said. “It’s hasn’t been real bad at any point. We’re not far away, that’s for sure. I need to test it in game situations and game speed and we’ll go from there.”

Nationals Manager Davey Johnson said that with a veteran player like Werth he is less concerned with the number of at-bats Werth got while on his rehab assignment and more about his leg muscle.

“I’m more concerned with him to see if he runs around and he doesn’t have that muscle spasms,” Johnson said. “I think he’s not going to have any of them. I’ve been texting with him back and forth. He’s been holding his food real good. He hasn’t been getting any spasms. So he should be ready. I think he’s going to be ready to play Saturday.”

Adam Kilgore contributed to this report.