Doesn't sound too serious based on this article from stlcardinals.com
PITTSBURGH -- Cardinals third baseman Scott Rolen was held out of the lineup on Wednesday, a day after being hit in the forehead by a Ryan Vogelsong fastball. Rolen is still bothered by a headache, though his other symptoms from what is being called a "mild concussion" have diminished since Tuesday.
John Mabry took Rolen's place at third base, while Jim Edmonds slotted from fifth into Rolen's usual fourth spot in the batting order. Originally, manager Tony La Russa made out a lineup that included Rolen, but head trainer Barry Weinberg and the Cardinals' medical staff decided that Rolen should be held out for another day due to his headache.
"He came in with some mild symptoms, just a little headache," said Weinberg. "But everything else has decreased. We're gonna give him a full workout and sit him today. Then we'll evaluate him tomorrow.
"If he goes through this full workout and tomorrow all the symptoms are decreased, he'll be OK to go."
Scott Rolen / 3B
Weight: 240 lbs
Bats: R / Throws: R
Stats | Splits
Manager Tony La Russa said it was possible that Rolen will be available to pinch-hit or even potentially play defense in the late innings. However, the team will try to be cautious with its five-time Gold Glove-winning, All-Star third baseman.
"The whole key to the workout is to see one, how the headache is, and two, his focus and stuff like that," said Weinberg. "See how he's focusing, make sure his eyes are OK and the headache doesn't increase. Then we'll take the next step."
Rolen is batting .348 with a .410 on-base percentage and a .625 slugging percentage. He has hit 13 home runs and leads the Majors with 53 RBIs.
Mabry has played primarily first base and outfield over parts of 11 seasons in the big leagues, but he has made 85 appearances at third base. He played five games at third for Triple-A Memphis before his recall on May 26. Other options for the Cards at third include Hector Luna and Cody McKay.
Matthew Leach is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.
Phew! Let's hope it's just precautionary.
[size=10]"Men are apt to mistake the strength of their feeling for the strength of their argument." [/size]