Because of a quirk in baseball rules, Anthony Rizzo is piling up 2B 'appearances'. He's up to 7 so far this year, and probably will hit 10 games 'appeared' at 2B sometime this season. These appearances are due to shifts and occur for one or two batters a game - not nearly evidence enough that Rizzo can actually man 2nd base.
Given the existing rules in the game, if Rizzo does get his official 10 games at 2B, he will be 2B-eligible. Much like Eric Thames, this situation raises the need to consider outs played per defensive position instead of games appeared when qualifying for positional eligibility. In the offseason, expect this to be visited in more depth.