The St. Louis Cardinals have had quite a number of players hit the disabled list this season; despite that, they're at .500 and very much in the NL Central race, just four games behind the first-place Cincinnati Reds.

They'll get reinforcements back for Friday's game against the Royals:

#Cardinals activate Jay, Matt Carpenter; option Adams, Chambers.

— Ken Rosenthal (@Ken_Rosenthal) June 22, 2012

Jon Jay has been out with a shoulder injury; Matt Carpenter with an oblique. Matt Adams is one of the Cardinals' better prospects, but they apparently want him to get more Triple-A seasoning. Adron Chambers is a spare-part outfielder who's been up and down between St. Louis and Memphis much of the last two seasons.

Jay went 3-for-7 in two rehab games with a home run. The Cardinals apparently figured that was enough to get him back in their lineup. Carpenter was 3-for-10 with Memphis in his rehab stint, also with a home run.

For more on the Cardinals, please visit Viva El Birdos and SB Nation St. Louis.