San Francisco (41-34) at St. Louis (41-37)

The San Francisco Giants are among baseball’s least productive offensive clubs, a fact the St. Louis Cardinals might have a hard time believing after they were hit hard in their series opener.

Repeating their outbreak at the plate won’t be nearly as easy.

The Cardinals will have ace Chris Carpenter(notes) on the mound Tuesday night at Busch Stadium, where he’ll square off with Randy Johnson(notes) and the Giants in a matchup of former Cy Young Award winners as the teams continue their four-game set.

San Francisco (41-34) came into St. Louis this week with the NL wild card lead, but a potent lineup hasn’t been what’s made it one of baseball’s most surprising teams. Instead, it’s been the major league-best 3.61 staff ERA that’s propelled the Giants despite a less-than-stellar offense that scores just 4.1 runs per game.

They averaged 6.5 runs in their last two contests in Milwaukee over the weekend, though, and that offensive spark carried over on Monday. Edgar Renteria(notes) and Travis Ishikawa(notes) each drove in three runs to support reigning NL Cy Young Award winner Tim Lincecum’s(notes) two-hitter in a 10-0 rout of the Cardinals (41-37).

“The way Timmy’s been pitching lately, after the first run I felt pretty comfortable,” said Ishikawa, who has four homers and nine RBIs in his last nine games.

The Giants improved to 25-5 when they score five runs or more. They’re also 19-4 when Renteria has an RBI, and the five-time All-Star has driven in a run in five consecutive games.

Carpenter (5-2, 1.78 ERA), who won the NL Cy Young Award in 2005, will have to hope for a better fate than he experienced in his most recent start. Matched up against two-time winner Johan Santana(notes), Carpenter gave up three runs and four hits over seven innings and suffered a 3-2 loss.

“The guy’s no slouch,” Carpenter said. “He knows how to pitch.”

Johnson (7-5, 4.68) does as well, and the 45-year-old left-hander has done a particularly impressive job lately. He’s 4-1 with a 2.57 ERA in his last seven starts, and gave up one run and six hits over seven innings Wednesday in a 6-3 win at Oakland.

“That’s a lot of innings for me. But I’m here to pitch on the day I’m here and I’m sure I’ll have a couple of bad games before the year is over,” the five-time Cy Young Award winner said. “In the meantime, you want to keep things rolling too.”

Johnson’s two starts against St. Louis last season didn’t go well. He went 0-1 with a 9.31 ERA, yielding five homers in 9 2-3 innings.

Albert Pujols(notes), who’s 9 for 21 (.429) lifetime with three homers and 10 RBIs against Johnson, hit one of the five. Ryan Ludwick(notes) also went deep against the Big Unit.

“A lot of us are young enough to the point where we were still in high school watching him pitch and dominate,” Ludwick told the Cardinals’ official Web site. “I remember a lot of his strikeout performances and obviously his run in the World Series with the Diamondbacks.

“I think anytime you face a guy who is going to be a Hall of Famer, it’s always fun. … It will be a challenge.”