Williams on Werth, Difo, Janssen and Rendon

Nationals manager Matt Williams will be without Jayson Werth for a while after the left fielder was officially placed on the 15-day disabled list due to the fastball he took off his left wrist in the second inning of Friday's win in San Diego.

"He's got a contusion," Williams said. "It's gonna be sore, it's gonna be swollen. It's still swollen. So we have to get that taken care of before he can even start back. Three days down already. Not really ready for a few more to even get back to swinging, and then working through that. So it's important for us to have a full 25 roster, and if he's gonna be down for another week before he can get back in the game anyway, then we're looking at 10 days."

Werth was slow to return to his normal form this year after coming off right shoulder surgery in January. He is slashing .208/.287/.294 this season, but Werth had picked it up on the recent trip out west as he was 5-for-15 with a homer before the setback. Rookie Michael A. Taylor will start in left tonight and is expected to get the majority of reps while Werth is out, with Tyler Moore and Clint Robinson as options as well.

To fill Werth's spot on the roster, the Nats opted to recall infielder Wilmer Difo from Double-A Harrisburg. In 33 games this season at Harrisburg and Single-A Potomac, Difo batted .315, with three homers and 18 RBIs.

"He's on our roster," Williams said. "He's one of our top prospects. And that being said, we've giving him an opportunity to come here and experience it. We do have pretty good coverage in the outfield with Michael and T. Mo and Clint. The issue that we have run into if we get down to it in a long game is that extra infielder. Given the fact that Jayson is down for a few days, we have coverage there, too."

Right-hander Casey Janssen was expected to rejoin the Nats this week after pitching last Friday and Saturday in Harrisburg, but the team decided to have the reliever make a few more minor league appearances this week before activating him. Janssen has been on the disabled list since the start of the season with right shoulder tendinitis.

"It's a matter of him getting out there and making sure he's hitting the ground running when he gets here because he's gonna be in leverage spots," Williams said. "He's gonna be in the back of our bullpen, a place where he's comfortable. We're gonna rely on him so I want to make sure that he's sure, that we're all sure that he's ready to go."

Janssen is expected to pitch tomorrow and Friday in Harrisburg.

"Pretty anxious," Janssen said. "Obviously I didn't expect to be hurt, period. So it adds to the frustration of not being with the team and helping, but should come quick. Hopefully, when I do get activated I can keep the momentum that they have built going and fit in."

Williams said he doesn't need to alter his rotation until May 26, with right hander Doug Fister currently on the 15-day disabled list with a flexor strain in his right forearm. The upcoming off-day Thursday gives Williams' starters the normal rest days between outings.

Infielder Anthony Rendon may join the team during this five-game homestand to continue his rehab. He's been working in Florida for the past week ramping up to baseball activities as he recovers from an oblique strain.