CLASH - Unranked player on enemy team?

Played Clash yesterday and after winning the first one the second team we played against had an unranked player on it? I thought we had to complete placements for one of the ranked type games. I'm not really sure if I misunderstood something but the League page for Clash it says "You need to have: Completed placements in at least one Summoner’s Rift ranked queue," so like does it count last season or something. Cause in the scouting phase his profile was empty and we didn't know who to ban and had to guess what role he was. It wasn't that big a deal but I feel like if someone like that was on my team I would be pretty annoyed. https://imgur.com/a/WeiQb