By NICOLINO DIBENEDETTO
(AP) -- The St. Louis Cardinals are on a tear at home and the San Francisco Giants may need to solve it to remain atop the NL West.
Lance Lynn looks to keep the Cardinals rolling by continuing his own unbeaten stretch Tuesday night against the Giants.
St. Louis (60-49) has won 12 of 13 at Busch Stadium behind an offense that has averaged 6.0 runs per game and batted .316.
That stretch showed no sign of ending Monday, when the Cardinals collected 12 hits to beat three-time All-Star Matt Cain and the Giants 8-2 in the opener of this four-game set.
"It's great to play at home with the atmosphere here," manager Mike Matheny told the team's official website. "This is a team that enjoys playing at home. The atmosphere, the crowd is second to none, so that plays into our hands."
Partly due to that home success, the Cardinals are within 2 1/2 games of Pittsburgh in the wild-card chase and six behind NL Central-leading Cincinnati.
The Giants (59-50) are in a more favorable position, sitting atop the West but only by one-half game over Los Angeles. That lead nearly became a deficit Monday, but the Dodgers fell 2-0 to Colorado.
Giving the ball to Lynn (13-4, 3.40 ERA) may keep the Cardinals surging, while potentially damaging San Francisco's status as division leader.
Lynn is 3-0 with a 2.70 ERA in his last five starts, allowing two runs or fewer in four including Thursday's 8-2 loss at Colorado. The right-hander did his part, giving up two runs in six innings before the bullpen was tagged for six runs over the next two.
Lynn has put together a strong stretch at home, winning four of his past five starts behind a 2.67 ERA with 33 strikeouts in 30 1-3 innings. He's thrown 12 scoreless innings to win his last two outings at Busch.
He did, however, struggle in his only appearance against the Giants, allowing five runs over 5 1-3 innings of a 12-7 home loss on June 2, 2011.
Jon Jay is looking to continue his own success at home, where he's hitting .367 this season compared to .217 on the road. The center fielder matched his career high set last month with four hits while driving in two runs Monday.
Jay has a career average of .467 in eight home meetings with the Giants.
Monday's loss ended a three-game win streak for San Francisco, which scored 35 runs during that run.
Buster Posey continued his torrid pace with two hits and an RBI. He's batting .468 with six homers and 25 RBIs in his last 19 games, and is 10 for 19 while connecting for three home runs and driving in eight in the first four of this seven-game road trip.
Posey has a .387 average in eight games against St. Louis, but is facing Lynn for the first time.
Barry Zito (8-8, 4.27) might need continued production from Posey after going 0-2 with a 7.56 ERA in his last three starts.
The left-hander struggled again Thursday, surrendering seven runs and six hits with three walks in 4 1-3 innings of a 9-1 loss to New York.
Zito is 1-6 with a 5.23 ERA in eight starts against the Cardinals, losing all three decisions in four games at St. Louis with a 9.00 ERA.
Updated August 7, 2012