It turns out that Cincinnati Reds slugger Ken Griffey Junior's chest soreness has been caused by pleurisy . That's an inflammation in the lining around the lungs.
He was kept out of Friday's starting lineup and is listed as day to day.
Griffey recently missed four games with an inflamed colon.
After missing most of spring training with a broken hand, Griffey has a .254 average with nine RBI's in 18 games this season.