Though back when I had that password my account was hacked. I'd wager this is just Gmail address+password combos collected from other leaks (read: not from Google). Really this just seems to be an attempt at sensationalizing.
Edit: it does the same on a much older account that I rarely use, too. Not the current password but the first two letters of what is likely a much older pw.
And the password was one of my lowest security "trash passwords" I use with this e-mail as login sometimes if it's a service I wouldn't trust or don't care if it's compromised.
So I wouldn't worry about this. Someone had their site hacked most likely and these are logins to the site, not from Google.