Thanks to the fact that a number of different archives of newswire photos are currently being auctioned on ebay, there are a number of fascinating images which are showing up for sale.
One of those images is a great shot showing the transition from the Seattle Pilots to the Milwaukee Brewers
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The photo is dated April 3, 1970 and was taken at the Pilots/Brewers Spring Training home in Tempe, AZ. The Pilots had just found out that they were going to move to Milwaukee a few days earlier (March 31), so it looks like this was a photo-op to show the changing of the uniforms from the Pilots to the Brewers.
There was apparently at least one other photo taken that made the newswire showing the new Brewers jersey:
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This photo was taken a few days earlier on April 1, and shows Marty Pattin in the same prototype jersey. The interesting thing about these pictures is that the Brewers jersey is not what they would wear when they started the season a few days later.
The letting on this jersey reminds me of the late 1960's California Angels jerseys (the "E"s look very similar):
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There is one other photo which shows this prototype design, but in this case its not being worn by a player, but by a stewardess:
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This picture is from the April 6 edition of
The Milwaukee Journal (so the picture would have been taken on the 5th).
So for at least a week, this version of the Brewers jersey was being used to promote the team's move.
However, when the Brewers were warming up on April 6, 1970 (the day before Opening Day) , they were wearing the uniform that was their standard home uniform for the 1970 season:
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Even though you can't make out the jersey entirely, you can see that the lettering is different and the stripes on the arm do not match the prototype.
For a full view of the jersey that was worn opening day, here is a picture of manager Dave Bristol after the Opening Day game
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Here we can see that the Brewers were wearing the uniform on Opening Day that would be their uniform for the entire season.
If anyone knows why the Brewers jersey that was used for the first week after the Pilots became the Brewers had a different design than what they ultimately ended up wearing that first season, I'd be interested in hearing the story.
Obviously there was a very tight window to get the new Brewers uniform created in time for Opening Day since the Pilots didn't become the Brewers until March 31, so could it be that the company that created the uniforms for the Brewers (possibly based in Milwaukee?) wasn't the same company that designed the prototype (who possibly may have been based in Arizona since the team was just finishing up Spring Training).
That seems like the most logical explanation, but I'm wondering if that has ever been verified.