ST. LOUIS -- Needing someone to fill the rotation void created by Jake Westbrook moving to the disabled list, the Cardinals have tabbed Tyler Lyons to start against the Reds on Monday.
Lyons shifts back to a starting role after a one-time cameo out of the Cardinals' bullpen. The rookie left-hander pitched two innings of relief on Tuesday, which will allow him to be plenty rested by the time he starts next week. It will be Lyons' eighth start for the Cardinals this season.
"Tyler has had a strong season," manager Mike Matheny said. "I like where he is right now and what he brings to our club. Here is a guy who has been consistent through this season and gives us a good shot. We've seen a couple real nice starts from him, and hopefully we get a few more."
The Cardinals have not committed to keeping Lyons in the rotation for the duration of Westbrook's absence as the veteran deals with a lower back strain, though Matheny noted that it was doubtful that the club would use an off-day next Thursday to skip that spot in the rotation the next time through.
Changing Lyons' role also puts a lefty back in the Cardinals' rotation just as the team prepares to face two division opponents who have been average against lefties this season. The Reds are 22-21 against left-handed starters, compared to 51-34 versus righties. Pittsburgh, despite being 23 games over .500, is 12-12 against lefties. If the Cardinals continue with this five-man rotation, Lyons would face the Pirates in back-to-back starts after Monday.
The Cards are 2-5 in Lyon's seven starts this season. He has posted a 5.35 ERA as a starter, and opponents have hit him at a .257 clip.
With Lyons needed in the rotation, the Cardinals have filled his bullpen spot with rookie Carlos Martinez. Martinez was added to the 25-man roster on Friday, the day he was scheduled to start for Triple-A Memphis. Matheny said that Martinez won't be designated solely as a long reliever, though he is stretched out if needed to pitch multiple innings.
Jenifer Langosch is a reporter for MLB.com. Read her blog, By Gosh, It's Langosch, and follow her on Twitter @LangoschMLB. This story was not subject to the approval of Major League Baseball or its clubs.