Martin O'Neill insists Aston Villa's decline during the final third of last season will remind everyone not to get carried away with their current success.
Villa were looking strong favourites for a top-four finish in February last season after opening up a five-point lead over main rivals Arsenal. But they lost momentum and had to be content with sixth spot.
O'Neill, whose side currently lie in fourth spot, said: "The same thing might happen again. We are on a decent run but the Premier League is very unforgiving."
He added: "Last season we were still going very strong in February time but lost a couple of matches in relatively quick succession.
"We lost to Chelsea, drew with Stoke and lost to Manchester City and we were rocked, knocked back and lost a bit of confidence.
"While we regained it eventually by finishing in the top six and getting into Europe - which I think is sometimes forgotten - we were unable to sustain the run.
"You are going along nicely, you win a couple of games but then you pick up a couple of injuries, lose a game and want to know where the next win is coming from.
"I think it's very much the case of same again. We are hanging in but we're playing well, with plenty of confidence. We are managing to win games when we go behind and when we get in front too.
"But I heard Harry Redknapp speaking the other day about how fickle it all can be.
"He said you can win two consecutive games and you're unbeatable and you lose a couple of games and you're useless. I think the same applies to us."
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