A match game of base ball was played at Gamble Lawn, Saturday evening, between the "Baltic" and "Young Commercial" base ball club, which was decided in favor of the latter (by a score of 34-25).
-Missouri Democrat, May 11, 1863
This is rather significant because, at the moment, this is the only record of a match game played in St. Louis during the Civil War (excluding the questionable April-June 1865 period). All other references are to intramural club games.
Not only was this game played during the war, it was played right in the middle of the war when things were as bad as they could be. The future of the Union, in May of 1863, was very much in doubt. To put it in context, the battle of Chancellorsville was fought during the first week of May and Lee launched his second invasion of the North on June 3. Gettysburg would be fought less then two months after this game was played. This game took place at the height of the war.
And just to add a bit more color, Stonewall Jackson (pictured above) died on May 10, the day before the game was played.
Another note of interest is the reference to the "Young Commercial" club. It's unknown if this is a reference to the Commercials, a junior auxiliary of the club or a completely unrelated club. One would imagine that the first or second option is most likely.