When Class AA starter and third-round pick Mike Mayers returned to the mound with two outs in the sixth inning Wednesday night, he found catcher Yadier Molina waiting for him. The big-league vet, considered by many the finest at his position in the majors, was there to give Mayers a quick breather before facing their final batter together.

Molina told Mayers to throw a sinker down and in, “hit your spot,” and then watch the righthanded batter roll a grounder to the third baseman to end the inning.

Mayers, 22, did just that.

“And the batter hits like a two-hopper to the third baseman. End of inning,” Mayers recalled Thursday afternoon. “We were both laughing about it.”

The prospect then paused and asked, smiling.

“Is it like that every time?”

Molina, the Cardinals’ Gold Glove-winning catcher, knew where the groundout was going Wednesday, knew where he was headed Thursday night and definitely knew where he intends to be tonight. After three more hits and a second successful rehab game with Class AA Springfield, Molina packed up his gear Thursday and, joined by his agent, hopped in a car, bound for St. Louis. The Cardinals won’t make an official move until today, but Molina said he’s ready to start tonight, seven weeks after he had surgery to repair a torn ligament in his right (throwing) thumb.

“Ready to go,” Molina said. “Everything responded very good. The way I expected. … Right now I don’t know what the deal is, but I’m ready (to start Friday). If not Friday, then it’s this weekend. Soon. I’m ready to go.”

The Cardinals open a four-game series against the archrival Cubs tonight at Busch Stadium, and including Saturday’s doubleheader this will slingshot them into a stretch with 30 games in 31 days. When Molina injured his thumb on a slide into third base on July 9, the Cardinals were 50-42 and two games behind the first-place Milwaukee Brewers. With Molina set to return, the Cardinals are 1 ½ games back, having gone 21-19 during their catcher’s 40-game absence.

Molina returns to the lineup with his .287 average and .409 slugging percentage, and he’s only the first of the reinforcements to arrive for the home stretch.

Michael Wacha will start Sunday for Double-A Springfield, and the next pitch he throws after that appearance could be in the majors. Wacha began his preparation for Sunday’s rehab start Thursday at Springfield’s Hammons Field, and he said after a 45-pitch live batting practice session Wednesday his body gave him a familiar and welcome affirmation of his improvement.

He was sore in all the right places.

“It’s not that same ache or soreness that I had right before I was injured,” said Wacha, who has been sidelined since June 17 with a stress reaction in his right shoulder. “It’s that good soreness that you get from going out there and pitching.”