By John Fay
The Cincinnati Enquirer

Barry Larkin continues to make progress and could come off the disabled list Saturday - the first day he's eligible.

"There's a chance it will be Saturday," Reds trainer Mark Mann said. "He ran (Thursday) pain-free. You want to be cautious with this type of injury."

Larkin almost certainly will be ready when the Reds open their six-game road trip Tuesday in Colorado. So who goes when Larkin returns?

In the starting lineup, Juan Castro probably will be out and Felipe Lopez will go to second base, although if Castro continues to hit, he'll be in the mix.

Whose roster spot Larkin will take is a tougher call.

The easiest Red to live without is Wily Mo Pena, an occasional pinch hitter who is unlikely to get any real playing time soon.

"We're so much in must-win mode," Reds manager Bob Boone said. "I'm trying to put out the best lineup to win."

But the Reds can't send Pena out without exposing him to waivers, so that's unlikely to happen.

The easiest move would be to return Ryan Freel to the minors. But Freel, who has added backup catcher to his duties, is a valuable guy to have around.

Reggie Taylor and Ruben Mateo could be on the bubble. Both have been given a chance since Ken Griffey Jr.'s injury. Both have struggled.

Mateo entered Thursday hitting .179 and was in an 0-for-12 slump. Taylor entered Thursday hitting .167 and was in a 1-for-16 slump.

They've been so ineffective that Jose Guillen started in right field Thursday. Taylor and Mateo are out of options. So like Pena, they must pass through waivers to be sent to the minors.

ON JUNIOR: Griffey was twirling the bat around as if he were in the lineup Thursday.

Griffey, on the DL with a dislocated right shoulder, continues to progress in terms of strength and range of motion. He'll be cleared for baseball activities as soon as he can go through the full range of motion without pain.

"It's hard to put a timetable on that," Mann said. "With him, it's two steps forward, one step back. After you increase the activity, you have to back off a little."

MORE INJURIES: More reports from Mann's training room:

• Russell Branyan is ready for the final stage of his rehab in Louisville. Branyan has played the last two games at first base. He'll play third base in the next few days to test his shoulder, on which he had surgery in October.

Branyan went into Thursday hitting .381 in 21 at-bats at Louisville.

• Jimmy Haynes is responding to treatment for his sore back. "He has less stiffness," Mann said.

• Luke Prokopec, the Rule 5 selection who has been rehabilitating his shoulder, will throw off the mound for the first time Tuesday. He has thrown 30 to 40 pitches at 50 to 60 percent.

• Pete Harnisch is healthy, but he's working on building arm strength after setbacks with a groin pull and a virus.

JUNIOR GOOD DEED: Griffey had a visitor from the Make-A-Wish Foundation at Thursday's game. Griffey gave 14-year-old Bret Botelho, who is suffering from a nerve disease, the full tour and introduced him to the other Reds.

GRULER OUT: No. 1 pick Chris Gruler will have surgery on his right shoulder Tuesday.

The arthroscopic procedure will be done at Good Samaritan Hospital. Recovery usually takes between a year and 18 months.

Gruler, who signed a $2.5 million bonus after being the third player taken in the 2002 draft, had shoulder problems at the end of last season and was put on a strengthening and throwing program.

But the 19-year-old right-hander was ineffective in two starts for Single-A Dayton, allowing 17 runs in 5 2/3 innings.

FARM REPORT: Louisville right-hander Seth Etherton went on the DL with a strained biceps muscle.