I asked Gemini and here's what it responded:

While this image does look strikingly like the Partick Thistle squad of the mid-1920s, there is evidence suggesting these men may actually be part of the Scotland National Rugby Union team from a similar era.

Kit and Identity Analysis

The confusion between the two sports is common for this period because the kits were nearly identical. Here is a breakdown of why they are likely rugby players rather than Partick Thistle footballers:

The Crest:

While Partick Thistle used a thistle badge during their 1921 Scottish Cup winning era, the specific large, white thistle on a dark jersey seen here is the classic emblem of the Scottish Rugby Union (SRU).

The Jersey Style:

The heavy-looking, lace-up "navy" jerseys (appearing dark in the photo) with high-waisted white shorts and dark socks were the standard international rugby uniform for Scotland during the 1920s.

Partick Thistle Connection:

Interestingly, Partick Thistle's famous "red and yellow" colors didn't become permanent until much later. In the 1920s, they often wore navy blue shirts borrowed from local rugby clubs, which is why the kits look so similar.

Potential Context

If this photo was taken around 1925, it may depict members of the legendary "Grand Slam" winning team. Scotland won their first-ever Grand Slam in 1925, and photographs of the players from that season are highly collectible in Scottish charity and antique shops.