ST. LOUIS -- Cardinals center fielder Randal Grichuk left Busch Stadium on Friday afternoon to undergo further tests on his back but returned ahead of the series opener against the D-backs with clearance to pinch-hit.
Grichuk exited the team's win on Thursday after three innings because of tightness in the lower left side of his back. After undergoing treatment on Friday afternoon, he went elsewhere to have another doctor examine the area of discomfort. He did not participate in any pregame work on the field but is considered an available option off the bench after passing all the necessary tests.
"They're just going to be cautious and continue to look at him and be ahead of this," manager Mike Matheny said. "We tried to get ahead of it last night. There was no sense to push."
Matheny confronted Grichuk after watching him run a little awkwardly around the bases and then in the field. Grichuk eventually confessed to having felt his back tighten up the night before while he was making a throw. He had hoped to play through the discomfort.
Grichuk missed a month last season after sustaining a back injury while squatting during a workout. It wasn't his first instance of injuring himself in the weight room, either. This injury, however, did not originate in that setting, Matheny emphasized.
Worth noting
• Jhonny Peralta began his Minor League rehab assignment on Friday by batting second and playing short for Class A Peoria. Peralta, who is moving around to various affiliates during his rehab stint, can remain in the Minors for up to 20 days before the Cardinals have to make a roster move.
• The Cardinals dug up a little more context regarding Matt Carpenter's six-RBI night on Thursday, finding it to be the fourth time in franchise history that a leadoff hitter has driven in that many runs in a game. It was previously accomplished by Shawon Dunston (2000), Augie Bergano (1945) and Taylor Douthit (1929).

• Hall of Fame manager Tony La Russa returned to St. Louis this weekend to attend the D-backs-Cardinals series. La Russa, who served as the Cardinals' manager for 16 seasons, now works as Arizona's chief baseball officer.
• The Cardinals' June 5 home game against the Giants has been picked up by ESPN for its Sunday night telecast, and game time has been changed to 7:07 p.m. CT. It will be the second time this season that the Cardinals will be featured on the Sunday night broadcast.