The 28-year-old was 2-1 with an 8.46 ERA in 42 games for the Atlanta Braves last season after making an opening-day roster for the first time in his career. He was 1-1 with a 3.38 ERA through June, then faded and was cut by the Braves in early August.
St. Louis agreed last month to a $500,000, one-year deal with free agent Trever Miller and claimed Charlie Manning off waivers. St. Louis had a lefty duo of Ron Villone and Randy Flores most of last year but didn't offer a contract to either pitcher.
A third left-hander, Tyler Johnson, also was not offered a contract after missing the season due to a shoulder injury.