Hill leaves Niners' practice early with back injury

SANTA CLARA, Calif. - Shaun Hill left the San Francisco 49ers' practice after throwing one pass Wednesday morning but said he is fine and will be ready to play in this weekend's exhibition game against the Dallas Cowboys.

Hill strained his lower back during practice Tuesday and received treatment.

"It was still there today," coach Mike Singletary said. "He probably could have pushed himself through practice, but I told him he didn't need to do that. Let the other guys get the reps and let's go."

Damon Huard and rookie Nate Davis, the team's fifth-round draft choice, alternated at quarterback the remainder of practice.

Hill shrugged off the injury. "I'll be fine," he said.

Singletary this week named Hill the regular season starter. Hill and Alex Smith had waged a tight battle for the starting role throughout the first three weeks of training camp.

Smith is out with a sprained thumb on his throwing hand and won't practice this week or play against the Cowboys. Smith started last week's 21-20 victory over the Oakland Raiders and injured his thumb while making a tackle after throwing an interception.

Singletary said he's not worried about how his quarterback situation will play out this week or the rest of the summer.

"It's not unsettling at all. Not one bit," he said, referring to the injuries. "We're going to Dallas and play football and not going to worry about who's not ready and who's hurt."

NOTES: DE Ray McDonald, who had reconstructive knee surgery during the offseason, has returned to full practice and has been taken off the physically unable to perform list. ... OT Adam Snyder is wearing a brace on his sprained right knee and wont play in the teams final two exhibition games. Newcomer veteran Marvel Smith has taken Snyder's place with the first-team offense. ... CB Tarell Brown has returned to practice after missing most of training camp with a toe injury. ... OG David Baas, who was hurt on the first day of training camp and hasnt practiced since, is close to returning to action. Tony Wragge has played well this summer with the starting offense in Baas place at left guard.