Updated

The St. Louis Cardinals kicked off perhaps a season- defining stretch with a big rally over a divisional opponent.

Having vaulted into first place in the National League Central, the Cardinals try to stay hot on Tuesday night as they resume a three-game set versus the Cincinnati Reds.

St. Louis saw Allen Craig hit a go-ahead grand slam in the seventh inning of last night's 8-6 win. The Cardinals' eighth victory in 10 games put them a half-game ahead of the idle Pittsburgh Pirates for first place in the division and also dropped the Reds 3 1/2 games out of the top spot.

Craig had three hits and Matt Holliday added a three-run homer for the Cardinals, who began a stretch of 13 straight games against Cincinnati and Pittsburgh.

"It's huge. There's a decent amount of games left, but in the grand scheme of things it's getting down to crunch time," Craig said. "Our schedule has been extremely tough. It doesn't get any easier. We needed to win this game."

Zack Cozart had three RBI and Todd Frazier connected on a two-run triple for the Reds, who have lost three of their last four and are 2-7 in their last nine versus the Cardinals.

Cincinnati held leads of 4-0 and 5-3 before St. Louis' big seventh inning and the Cardinals have now won nine of the 13 overall meetings this year.

"We had opportunities, we had some chances. It makes it tough when you're one out away," Reds manager Dusty Baker said.

Cincinnati is still six games ahead for the second wild card spot in the NL and have ace Mat Latos on the hill tonight.

Latos battled illness last time out to beat Arizona on Thursday. He allowed a run on five hits over eight innings, striking out six without a walk. It marked the seventh straight start he allowed two earned runs or fewer, with the righty 5-1 with a 1.47 earned run average in that span.

"He's grown up before our eyes," Baker said of Latos, who was vomiting before and during the game. "He did what aces do."

Latos is 13-4 with a 2.93 ERA in 26 starts this season and has had success versus the Cardinals this season. In three previous starts, the 25-year-old is 2-0 with a 1.42 ERA, having held St. Louis to three earned runs over 19 innings.

The Cardinals have gotten a big boost from Joe Kelly, who starts tonight having gone 5-0 with a 2.33 ERA in eight starts since being put in the rotation full-time in early July.

The 25-year-old righty, who has not suffered a loss since a June 5 start versus Arizona, won his second straight outing on Thursday as he held Atlanta to a pair of runs on seven hits and two walks over six innings.

"I didn't have any of my good stuff today," admitted Kelly, who is 5-3 with a 3.01 ERA in 30 games (9 starts) this year. "I just went out there and just tried to battle the whole time. Nothing was easy."

Kelly has not faced the Reds this season and will make his first career start against them. He went 1-0 with a 1.80 ERA in two relief encounters a season ago.