The Giants have now lost seven straight at Great American Ball Park, as they look to avoid a sweep against a hot Reds team in a Thursday matinee.
Homer Bailey gets the ball for Cincinnati, and he'll face San Francisco's Ryan Vogelsong in a battle of a couple of pitchers who went seven innings in their last starts.
Bailey earned his first win of the season his last time out, a 9-4 victory at Wrigley Field against the Cubs. He was staked to an early lead and worked quickly in allowing four runs -- only one earned -- in seven innings.
"I was trying to get out there, get back in the dugout as quick as I could, especially with the way we were swinging it today. Keep our guys warm," Bailey said afterward.
Bailey has faced the Giants four times in his career, going 1-0 with a 6.35 ERA.
Vogelsong is still in search of his first win, despite a pair of quality starts this season.
Reds manager Dusty Baker has already said Scott Rolen will be rested in a day-game-after-night-game situation and that Todd Frazier will start at third base. The move is somewhat curious as in 12 plate appearances against Vogelsong, Scott Rolen is hitting .400 with a double, a triple, a homer and six RBIs.
Prior to Thursday's game, Reds first baseman Joey Votto will be honored with the Canadian Baseball Hall of Fame's Tip O'Neill award for the second straight year. The award goes to the top Canadian player.
Giants: Huff to DL with anxiety troubles
The Giants placed Aubrey Huff on the disabled list after manager Bruce Bochy revealed Wednesday that the veteran has been dealing with anxiety attacks.
Huff had missed the three previous games, last playing Saturday, making his first career appearance at second base. He is hitting just .182 on the season, with just one hit in his last 15 plate appearances.
"He had an episode of anxiety. He got some treatment and will continue to get treatment," Bochy said. "We can't keep going short, so we think at this time the best thing is to go ahead and make this move and put him on the 15-day disabled list." With Wednesday's loss, the Giants snapped a streak of four consecutive series victories. The last time they lost a series was also the last time they were swept -- a three-game set to open the season in Arizona.
Reds: Stubbs leads off for a day
Center fielder Drew Stubbs was back in the leadoff spot Wednesday, with Zack Cozart getting the night off. Stubbs went 1-for-3 with a walk.
"It's the same approach. I'm not going to change anything," Stubbs said. "You could argue that hitting in front of Joey, you get more pitches to hit. Maybe that got me going but at the same time, it's a coincidence that I settled in and found my stroke a little bit."
In the previous six games as the No. 2 hitter, Stubbs batted .385 (10-for-26) with a homer, two doubles and six RBIs.
Reds reliever Nick Masset had an MRI exam on his right shoulder that has forced him to miss the first few weeks of the season. Masset said he is "making some big steps toward being healthy."
In nine at-bats against Vogelsong, Reds second baseman Brandon Phillips has five hits.
The Giants' last victory at Great American Ball Park was a 3-0 win on June 8, 2010.