--RHP Jose Valverde, who led the NL in saves with 44 last year and the entire majors with 47 in 2007, was unavailable Thursday for the Astros' first save situation.

A day after giving up one run in relief in the Astros' 4-1 victory, Valverde couldn't take the ball because of a sore back Thursday in the victory over the Pirates. "We have to take care of these guys when we can, and it's good for us that we do have guys that are capable in our 'pen to come and close out ballgames and on our bench to play for us," manager Cecil Cooper told the Houston Chronicle.

--RHP LaTroy Hawkins, who had his first scoreless outing Wednesday after giving up runs in his previous outings of the season, threw a scoreless ninth inning Thursday against the Pirates to convert the save. Hawkins lowered his ERA to 4.50.

--INF Jeff Keppinger, whom the Astros were counting upon because 2B Kaz Matsui is out with back soreness, exited early Thursday with a sore back.

Matsui, who missed most of the last two months of last season, was out of the starting lineup for the second consecutive day with a sore back.

Matsui missed the last two games of the Pirates series. And although the Astros were off on Tuesday, his three days without playing don't appear enough for him to be healthy and start on Friday.

"Each day he gets better," manager Cecil Cooper told the Houston Chronicle. "The key for us is to make sure he's healthy. He's a key for us."

MEDICAL WATCH:

INF Jeff Keppinger (sore back) left the April 16 game. He is questionable for the April 17 game.

2B Kaz Matsui (stiff back) did not play April 15-16, and he is unlikely to play April 17.

RHP Jose Valverde (sore back) was unavailable April 16.

RHP Brian Moehler (strained right knee) went on the 15-day disabled list retroactive to April 14.

RHP Doug Brocail (strained right rotator cuff) went on the 15-day disabled list retroactive to April 11.

RHP Brandon Backe (strained left side muscle) went on the 15-day disabled list March 27. He threw off a mound April 8 and April 11.

INF Aaron Boone (open-heart surgery on March 26) went on the 15-day disabled list March 27, and he was transferred to the 60-day DL on April 10. He was uncertain whether he'd resume his career.

ROTATION:

RHP Roy Oswalt

LHP Wandy Rodriguez

LHP Mike Hampton

RHP Russ Ortiz

BULLPEN:

RHP Jose Valverde (closer)

RHP LaTroy Hawkins

LHP Wesley Wright

RHP Geoff Geary

LHP Tim Byrdak

RHP Chris Sampson

RHP Jeff Fulchino

RHP Alberto Arias

CATCHERS:

Ivan Rodriguez

Humberto Quintero

INFIELDERS:

1B Lance Berkman

2B Kaz Matsui

SS Miguel Tejada

3B Geoff Blum

INF Jeff Keppinger

INF Jason Smith

OUTFIELDERS:

LF Carlos Lee

CF Michael Bourn

RF Hunter Pence

OF/1B Darin Erstad

OF Jason Michaels