Former Chelsea defender Glen Johnson has encouraged Saul Niguez to cut short his loan.
The Atletico Madrid midfielder has hardly featured at Chelsea since his August arrival.
Johnson, 37, told Bettingodds.com: "There's no point at being on loan somewhere and not playing. It's hard enough to accept not playing when you're on a contract.
"People forget that the purpose of going on loan is to prove yourself, so going on loan and not playing completely defeats the object.
"If he doesn't get enough of a run in the side then of course he should go back to Atletico Madrid.
“Sometimes the Premier League can just kill people. Sometimes you can stroll around in other leagues and get away with stuff, so if you're doing that in other leagues then you're going to get found out in the Premier League.
"I'm not necessarily saying that's happened to Saúl but many players come to the Premier League and don't hit the ground running."