--LHP Joe Beimel was placed on the 15-day disabled list with a strained left hip flexor after injuring himself while making a nice diving catch of Braves 2B Kelly Johnson's drag bunt in the eighth inning of Monday night's 3-2 win. Beimel had been one of Washington's only effective relievers to date, posting a 1.23 ERA and four holds through his first eight appearances. He was replaced by RHP Saul Rivera, who had just been optioned to Class AAA Syracuse after blowing a ninth-inning lead Sunday. Rivera, who had 72 hours to report to the minors, hadn't left Washington yet and thus was available to return immediately.

--2B/OF Willie Harris (strained left oblique) is set to begin a rehab assignment with Class AAA Syracuse. Harris, who hurt himself fouling off a pitch April 12, expects to be ready to come off the disabled list when he's eligible on April 28.

--SS Cristian Guzman (strained hamstring) is due to begin playing at extended spring training Wednesday, the first step toward his return to the Nationals' lineup. Guzman likely will join one of Washington's minor league affiliates for a rehab assignment before coming off the 15-day DL. He's eligible to return April 29, and team officials believe he'll be ready by then.

MEDICAL WATCH:

LHP Joe Beimel (strained left hip flexor) went on the 15-day disabled list April 21.

SS Cristian Guzman (strained left hamstring) went on the 15-day disabled list retroactive to April 14. He will go on a minor league rehab assignment but should be back after missing just 15 days.

2B/OF Willie Harris (strained left oblique muscle) went on the 15-day disabled list April 13. He was set to begin a rehab assignment with Class AAA Syracuse during the week of April 20-26.

OF Roger Bernadina (broken right ankle) went on the 15-day disabled list April 19. He had surgery April 18, and he will miss a minimum of two months before beginning a rehab assignment.

1B Dmitri Young (strained back and hip) went on the 15-day disabled list retroactive to April 1. Young, who has been working himself back into shape while trying to manage diabetes, will remain at extended spring training in Viera, Fla. The Nationals hope he'll be ready to go on a rehab assignment at some point in late April and perhaps return to the big-league roster soon after that.

RHP Terrell Young (inflamed right shoulder) went on the 15-day disabled list retroactive to March 27. He started a throwing program at extended spring training in early April.

LHP Matt Chico (Tommy John elbow surgery in July 2008) went on the 60-day disabled list March 28. He will miss at least the first half of the season.

ROTATION:

LHP John Lannan

LHP Scott Olsen

RHP Daniel Cabrera

RHP Shairon Martis

RHP Jordan Zimmermann

BULLPEN:

RHP Joel Hanrahan (closer)

RHP Julian Tavarez

RHP Mike Hinckley

RHP Saul Rivera

RHP Garrett Mock

RHP Jason Bergmann

RHP Kip Wells

CATCHERS:

Jesus Flores

Wil Nieves

INFIELDERS:

1B Nick Johnson

2B Anderson Hernandez

SS Alberto Gonzalez

3B Ryan Zimmerman

INF Ronnie Belliard

INF Alex Cintron

OUTFIELDERS:

LF Adam Dunn

CF Elijah Dukes

RF Austin Kearns

OF Josh Willingham

OF Justin Maxwell