ST. LOUIS -- Bothered by a sore left hand, Cardinals center fielder Carlos Beltran did not start Tuesday's series opener against the Astros.

Manager Mike Matheny didn't go into many specifics about the injury, saying only that Beltran's hand has "been bothering him for a while now." Tuesday, though, marked the first time that the injury was cited as a reason for Beltran not starting.

Beltran was not in the lineup on Saturday, either, though Matheny described that absence as related to general fatigue.

Beltran, who was available to pinch-hit on Tuesday, is 4-for-23 with two RBIs in the first six games of the homestand. His .237 average since the All-Star break has dropped his season average to .278. He leads the National League with 85 RBIs and trails only Ryan Braun in home runs. Beltran has hit 28, while Braun has gone deep 33 times.

With Beltran on the bench, Jon Jay started in center field and Allen Craig started in right field, shifting into the cleanup spot. Matt Carpenter earned the start at first base.

Prospect Miller unlikely to contribute this year

ST. LOUIS -- Adjusted mechanics and an altered mindset have helped Shelby Miller, the organization's top pitching prospect, turn his season around in Triple-A. But is it enough to warrant a stay in St. Louis late this season?

As the Cardinals consider which players they want to add to the roster in September -- a month in which clubs are free to carry as many players from their 40-man rosters as they would like -- Miller's name is an intriguing one. Projected as an eventual top-of-the-rotation starter, Miller wouldn't break into the Cards' rotation this year. That doesn't mean, though, that he couldn't be added to the 'pen.

But general manager John Mozeliak downplayed that likelihood, describing it as "not likely" that a player not currently on the team's 40-man roster would be added for the purpose of bringing him up for a stretch run.

Asked specifically about Miller's chances, Mozeliak added: "I hate to get into specifics about potentially what we may or may not do on an individual, but I would recognize that he's pitched extremely well, had another very strong outing [on Tuesday] and that's great to see. How that plays into our decisions for September call-ups, it will factor into it, but ultimately we have to make sure if we're willing to start the [Major League service time] clock on somebody, are we going to use them or not? That's always the question you have to ask yourself when you make that decision."

Miller struck out 12 in a seven-inning start on Tuesday, giving the former first-round Draft pick 50 strikeouts in his last seven starts (42 2/3 innings). In that same span, Miller has walked just one. But his season ERA sits at 5.04, a reflection of the challenges Miller has had at the Triple-A level this year.

Worth noting

• Asked to throw 87 pitches in relief during Sunday's 19-inning game, Joe Kelly will be unavailable out of the bullpen for at least the first two games of this series. Though that leaves the Cardinals with a relief corps of only six, the organization did not strongly consider making a roster move to bring up another pitcher.

• Lance Berkman is expected to begin his Minor League rehab assignment with Triple-A Memphis on Friday, not Wednesday, as the first baseman initially projected. The schedule change is not due to any setback, but instead gives Berkman a few extra days to continue his workouts in St. Louis.

The Cardinals will not activate Berkman, who has been on the disabled list with right knee soreness, any earlier than Sept. 1. By waiting until September, the club would not have to worry about making a corresponding roster move.

• Jacob Wilson (New York-Penn League) and Trevor Martin (Appalachian League) earned Minor League Player of the Week honors for their respective leagues on Monday.

Wilson, a 10th-round pick in the 2012 First-Year Player Draft, went 8-for-16 with three homers, four runs scored and eight RBIs in four games last week. Martin, a 2010 Draft selection, finished 9-for-20 with four home runs, 10 RBIs and eight runs scored.