SAN FRANCISCO -- The Giants are continuing to mull the final details of their 25-man roster for the National League Division Series, with manager Bruce Bochy saying Thursday that a final decision will likely be announced Friday.

Among the decisions the Giants will have to make is the balance between position players and pitchers on the roster, with the Giants likely having to decide between taking 13 or 14 position players.

"We pretty much have it in our heads which way we're going to go, but we still have a little bit of time before we make that decision," Bochy said. "And of course, a lot depends on which way we go on the position side -- whether we go with, for example, an extra catcher, [Aubrey] Huff, [Francisco] Peguero, those guys here. So we'll announce that probably the next day or so."

Outside of their usual starters, Bochy said Ryan Theriot, Joaquin Arias, Hector Sanchez and Xavier Nady will be on the roster, with all of them being right-handed batters besides Sanchez, who is a switch-hitter. Huff is a candidate to make the roster as a left-handed pinch-hitting option, though Huff's addition to the roster likely means the Giants would want to add another speed option as well, such as Peguero, Justin Christian or Emmanuel Burriss. "So that's what we're talking about, making sure we're covered on the left side," Bochy said. "We know they have some good lefties on the back end of the bullpen. They also have a good righty. So you want to make sure you're covered."

Bochy has also said the Giants will take all five starters on their roster, though only four will start, with one being used out of the bullpen.

The addition of a starter in the bullpen, Bochy said, will not alter his committee approach to his relieving corps, with Sergio Romo, Javier Lopez, Jeremy Affeldt and Santiago Casilla continuing to get the bulk of the late-inning work.

"We'll use everybody, and we've done a great job doing it," Bochy said. "We now have at least have one long guy to help us in the bullpen and give us coverage there, but I'm not really going to be making any changes now because it's been working. Romo, Lopez, Affeldt and Casilla will all be used in the eighth and ninth, and possibly the seventh."

Giants officially tab Bumgarner for Game 2 start

SAN FRANCISCO -- The Giants officially named Madison Bumgarner as their starter for Sunday's Game 2 of the National League Division Series against the Reds, with the 23-year-old left-hander following up ace Matt Cain, who will pitch for the Giants in Saturday's opener.

Manager Bruce Bochy had spoken to Bumgarner about getting the Game 2 start for the last week, but Bumgarner didn't get the official word until Thursday. Bumgarner went 16-11 with a 3.37 ERA in 32 starts this season.

"This is what you work so hard in the offseason for, and you get a chance to have it all pay off," Bumgarner said after throwing a bullpen session during Thursday's voluntary workout.

Reds vs. Giants

The promising young left-hander has a veteran's worth of postseason experience already, having played a prominent role in the Giants' 2010 World Series run, including throwing eight shutout innings against the Rangers in Game 4 of the World Series.

This time around, Bumgarner will join Cain in being tasked with defending the Giants' home field under this year's Division Series setup, in which the lower seed hosts the first two games.

"If you look at the years that Matt and Madison have had, that's why they're going Game 1 and Game 2 right now, and that's usually how you do it," Bochy said. "Sure, sometimes you make adjustments when you're going on the road, but we feel like these two have earned these starts, and that's why they're going out there."

Bumgarner will be opposed by the Reds' Bronson Arroyo after Cain duels Johnny Cueto in Game 1. The last time Bumgarner faced the Reds, he tossed a one-hitter for his first career complete game.

"This is the postseason. You can't pay attention to what happened in the regular season, whether it was good or bad," Bumgarner said. "You have to go out there and try to make pitches every time and do what you've got to do. That game, fortunately, I was able to do that. I had some things going my way, and you have to just go out there and try to compete and keep us in the game."

Worth noting

• Dusty Baker stopped by the Giants' voluntary workout Thursday, chatting by the batting cage with Bochy, general manager Brian Sabean and former Giants manager Felipe Alou. Baker, the former manager of the Giants and current Reds skipper, returned to the team Monday after recovering from a mini-stroke and irregular heartbeat.

• Freddy Sanchez took the field with the Giants during Thursday's workout, joining his teammates after having spent the last few weeks rehabbing at the Giants' complex in Scottsdale, Ariz., following shoulder problems in Spring Training and a back surgery in July.

• The Giants and KNBR 680 will host a noon-time rally at Willie Mays Plaza on Friday.