The Cardinals just designated Komatsu for assignment, and if he clears waivers, must be offered back to the Nationals.
Komatsu was taken by the Cardinals from the Nationals in December's Rule 5 draft. He was originally acquired by Washington last year from Milwaukee in the Jerry Hariston Jr. trade.
There's a chance another team claims Komatsu - who hit .211 in 19 at-bats with the Cardinals this season - and puts him on its 25-man roster.
The Cardinals and Nationals could also work out a trade which would allow St. Louis to hold onto Komatsu.
Something to monitor over the next 10 days.
Meanwhile, here's a cool note: If/when Bryce Harper hits a home run this season, he'll be the first left-handed hitting teenager to go yard since Ken Griffey Jr. did so for the Mariners back on Sept. 20, 1989.