The ball, in this art, was formally opened for the season yesterday, by the Union Club, at their new grounds on Grand avenue, near the Fair Grounds. The attendance was not particularly large. The first nine played a match game with the strongest nine on the field. The new grounds of the club are 525x500. They are not very level nor, as it seems to us well adapted, in this and other respects, to the game. A stand has been erected for the accommodation of visitors, underneath which there is an interesting cave.
It is said by those who claim to be au fait on base ball matches that an interesting season of the game is coming, and that this interest will be awakened by the arrival of clubs from New York, Ohio, Illinois and Indiana. The understanding is, as it is reported, that the clubs will play fair-test matches. It was said yesterday among those who discussed the subject that the game could well receive the best of attention this season, as the young men interested in it had not any pressing degree of any other occupation to engross their time and attention.
-Missouri Republican, May 3, 1868
What we have today is the first game ever played at the Grand Avenue Grounds. This is a rather significant event and I'm surprised I never bothered to dig it up before. The top clubs in St. Louis would play baseball at this site for the next hundred years.
The other interesting thing in this article is the mention of the fact that the players "had not any pressing degree of any other occupation..." This lends some support to my idea that players for the top St. Louis clubs were being compensated in some form by 1868.