CINCINNATI -- On a day when the Cardinals made six pregame roster moves, they added a seventh to the daily docket on Tuesday, when it was announced after a 7-5 loss to the Reds that lefty Tyler Lyons was placed on the 15-day disabled list. The move is retroactive to Saturday.
Manager Mike Matheny revealed after Tuesday's game that Lyons had been dealing with discomfort in his right knee since last week. The Cardinals tried to limit Lyons' usage while he underwent treatment, but a scan of Lyons' knee revealed that he has a stress reaction.
With Lyons coming off the 25-man roster, the Cardinals then recalled Dean Kiekhefer on Wednesday. The lefty was demoted to Triple-A Memphis as part of a series of moves on Tuesday, but he was told to remain in Cincinnati until after Lyons could have an MRI. Once that confirmed the diagnosis, Kiekhefer was added back to the roster.

"It's something [Lyons] has had for a while," Matheny said. "It kept progressing, and we weren't seeing it get better, and then it actually got a little worse to where he couldn't get [his knee] fully extended."
Matheny did not guess on a timeframe for recovery, but he noted that Lyons is "going to have to be off it for a good little while, a few weeks at least." The Cardinals do anticipate Lyons returning this year.
Lyons' lack of availability on Tuesday complicated things for Matheny, who had to deploy five other relievers to cover behind Adam Wainwright's five-inning start. It also explains why the Cardinals chose to start Jaime García on short rest last Saturday instead of giving the spot start to Lyons.
When Lyons appeared in relief that day, he allowed two runs on two hits and a walk in two-thirds of an inning.
Worth noting
• Matt Carpenter (right oblique strain) was scheduled to wrap up his rehab assignment with Double-A Springfield on Wednesday and then travel to St. Louis on Thursday in preparation of being activated from the DL before Friday's game against the Braves. In his first three games of that rehab assignment, Carpenter went 4-for-8 with a double and home run.
• The Cardinals chose right-hander Matt Pearce and shortstop Allen Cordoba as their Minor League Pitcher and Player of the Month, respectively, for July. Pearce went 2-3 with a 1.93 ERA in six starts with Class A Advanced Palm Beach. He had two complete games, walked only two all month and led all Minor League pitchers with 46 2/3 innings.
Cordoba hit .376 with five doubles, three triples and eight stolen bases while playing for Rookie-level Johnson City. Cordoba ended the month on a 12-game hitting streak.
• The Cardinals announced plans to host "An Evening with 2006 Greats" at Busch Stadium on Aug. 22. David Eckstein, Jim Edmonds and Randy Flores will all be on hand to tell stories and share memories of the club's 2006 World Series championship season. To learn more about the event and/or to purchase tickets, visit cardinals.com/greats.