Since Fifa 17, so-called Ones to Watch (OTW) player cards have been available for purchase. These cards get an update every time the player has performed well in the past week and is thus accepted into the team of the week.
However, these cards can be traded very well by traders by buying them whenever the player has performed poorly in the past week. This is because no one expects these OTWs to increase this week, causing the price to drop.
However, as soon as the next game is due and the player is in the starting eleven, many traders expect a better performance, which increases interest in the OTW card, and therefore the price goes up. Using this method, you can make a profit every week by buying the right OTW players.