~ The Rams may replace struggling rookie Ryan Fitzpatrick with veteran Jamie Martin.

ST. LOUIS -- Three games ago when Ryan Fitzpatrick got the St. Louis Rams' starting quarterback job, interim coach Joe Vitt kept his choice under wraps most of the practice week.

Vitt is back to his old tricks this week, refusing to say whether the struggling rookie or 35-year-old backup Jamie Martin will get the call against the San Francisco 49ers. He said he's made his decision "but I'm not going to announce it."

Vitt said his pick will be the player "who I think will give us the best chance to win."

It's likely to be Martin, who replaced Fitzpatrick in the fourth quarter of last week's 17-16 loss to the Eagles, even though he wasn't able to rally the Rams (5-9) to a victory. Fitzpatrick threw three touchdown passes in his NFL debut to rally his team past the Texans, but in his three starts he has only one touchdown pass and a low passer rating of 58.2.

Starter Marc Bulger was placed on injured reserve earlier this week.

The feature back also is a bit of a question mark with Steven Jackson missing practice for the second straight day due to a hip pointer on his left side. Jackson, listed as probable, missed much of the second half last week because of the injury.

Jackson, who topped 1,000 yards rushing last week, said it was a day- to-day proposition. He said the injury had improved somewhat but didn't feel like he had his normal burst of speed.

"I'm not a doctor. I'm not a miracle worker," he said. "I'm going to try to help my team in pursuing another win, but I've got to make sure everything is OK."

Vitt said he'd rely on Jackson.

"I think he'll be OK," the coach said. "If he tells me at game time he's ready to go, I trust him."

Noteworthy

* Offensive linemen Ryan Tucker and Claude Terrell both missed practice with flu-like symptoms. Safety Jerome Carter missed Wednesday's practice with a similar illness.

* Vitt, who's been relentlessly upbeat in his opening post-practice statements, was more realistic on Thursday. "We had a good workout today," he said. "Then again we had a good workout this time last week. I hope it transpires to a win."

* Mike Martz, who stepped down for the season in October due to a heart ailment, attended part of practice. He's been cleared to return to duty on Jan. 1, but he and the Rams are likely to reach a settlement for the final year of his contract. Asked what he wanted for Christmas, Martz joked: "A job."