"I left it a little too much out over the plate," said Hoover, who has allowed three grand slams this season. "I knew he's a good hitter with the bases loaded and I didn't want to come in there on the first pitch."
Cincinnati manager Dusty Baker said Craig's drive was "devastating."
"They have a lot of dangerous hitters, but we helped them out with a couple walks," he added.
Craig improved to 14 for 31 (.452) in his career with the bases loaded. He is batting an eye-popping .452 with runners in scoring position this year, a big reason why he leads St. Louis with 95 RBIs.
"No bigger or better at bat all season," Matheny said. "He's been so good in that situation."
The crowd of 35,159 roared as Craig rounded the bases. The big first baseman then came out for a curtain call.
"I wasn't thinking about hitting a home run, I just wanted to hit it hard and in play," Craig said. "When guys are on, I just try and hit it hard somewhere and it usually works out."
Craig's drive helped the Cardinals rally from a four-run deficit, tying their largest comeback of the season. They also came from four down to beat Pittsburgh 6-5 in 12 innings on Aug. 15.
Bruce connected against Seth Maness, but that was it for Cincinnati, which lost for the third time in four games.
"We're getting down to crunch time and every series is important," Hoover said. "When you look back at the end of the season, one loss could be important."
Lyons settled down after the rough start and was charged with one earned run in five innings. He struck out a career-high seven and walked two.
"The second inning didn't go how I wanted it to," Lyons said. "It was just about bouncing back and trying to keep the team in the game for as long as possible. I think I did that."