PITTSBURGH -- Unable to will his arm to loosen enough to allow the pitches to come freely and the velocity to rise, Adam Wainwright endured another early exit in Thursday's 11-7 win over the Pirates, returned to St. Louis for medical tests on Friday and was placed on the 10-day disabled list with a right elbow impingement.
The Cardinals recalled right-hander Mike Mayers from Triple-A Memphis to fill the open roster spot.
"It's real disappointing because this time of year, what are we, [1 1/2 games] back? This is usually when I go," Wainwright said after allowing five runs in a three-inning, 55-pitch start. "In my whole career, this is when I take off and pitched some really good baseball. It's hard for me to look my guys in the face and tell them that I'm sorry it just wasn't as good as it needed to be."
Luke Weaver, who pitched two scoreless innings in relief of Wainwright on Thursday, will slide into his rotation spot. The severity of Wainwright's injury will be known after his visit with Dr. George Paletta on Friday evening. However, the Cardinals did not feel it necessary to wait that long to make the roster move.
"Just based on how he felt, given the elbow impingement, it just made sense to put him on the DL," Cardinals president of baseball operations John Mozeliak said. "We're hopeful it's just rest and we go from there. But we'll know more [Saturday]."

The same sensation in the back of the arm that plagued Wainwright in his last start inhibited him again. Wainwright compared it to the discomfort he pitched through in 2014. He underwent surgery to remove bone spurs at the end of that season.
Before leaving Pittsburgh, Wainwright said he believes rest -- not surgery -- will be the remedy now. The unknown, though, is how long a period of rest he may require.
"When I bring my arm back and I move forward, the back of my elbow joint has a real hard pinching sensation," Wainwright said. "It's nothing I can grit through. I'm trying my best. I'm gritting my teeth and doing everything besides sticking a stick in my mouth to try and get some more out of it. It's one of those things where your body just won't let you fight through it as much as you want it to."
Since pitching a season-long 7 2/3 innings on July 22, Wainwright has been hampered by a series of physical ailments. Back tightness landed him on the DL, after which a cut on his right middle finger limited his effectiveness upon returning. His arm hasn't been right in these last two outings, something which the radar gun has made evident.

After averaging 90.2 mph on both the four-seamer and sinker through his July 22 start, Wainwright has touched as high as 89 mph in his last two appearances. Wainwright averaged 85.9 mph with his sinker on Thursday. The average velocity of his cutter has dropped to 78.7 mph.
Over his last two starts, opponents swung and missed at four of Wainwright's 132 pitches. All combined, Wainwright has permitted nine runs on 15 hits and nine walks in 11 innings this month. He has one strikeout during that stretch.
"It just didn't get better like we wanted it to," Wainwright said. "It doesn't hurt in everyday life, just when I'm pitching. Unfortunately, I'm a pitcher for a living.
"I knew it was going to be a grind all week. That's why I didn't throw much in between. I didn't throw my bullpen session. I tried to save some bullets, and it just didn't respond like I wanted it to."