After you have taken into consideration & understood what Dman2pt & Leandra explained, then you can try to keep the two players for one season and see how they perform the next season. I have had players who simply do not want to play well but I bench them, train them (if fast trainer) and they usually pick up the second season. I've also had players who play 5 matches and rate 5 but I persisted with them (due to the fact that I stop myself from buying players on day 7 - transfer window) and they deliver.