Torres has not scored a league goal for Chelsea since before Christmas, although the Europa League has proved more to his liking with his goals taking his side to the verge of the final.
Thursday's 2-1 victory in Basel, in which Torres struck the woodwork, makes them favourites to go through, although Sunday's Premier League home match against mid-table Swansea is arguably more important with Chelsea in a scrap for third and fourth spots with Arsenal and Tottenham Hotspur.
Hernandez, who has played alongside Torres for Spain, believes the Chelsea striker is close to re-discovering the kind of form he displayed at Liverpool.
"He is a big player. Sometimes, in football, the big players go through bad moments and don't play at their best, but it does not mean they are not still big players," Hernandez told the Walesonline website.
"All strikers love scoring goals. He went through a spell of not scoring goals and people criticised him.
"But Fernando has always been a big player and I think he will get back into the national team in the future.
"He's still an important player for the national team."
Hernandez believes the arrival of Rafa Benitez at Stamford Bridge has helped Torres regain his confidence.
"He's had his moments this season and in other seasons where he hasn't had that confidence. But when he has confidence he's a top player," former Valencia winger Hernandez said.
"I think Rafa is a help for him. The best moments for Fernando were with Rafa at Liverpool. He is a manager who seems able to help Fernando," he said.
"And I think you can see he has recovered his confidence in the last few months and games and now is a better moment for Fernando. But I hope he has a quiet day against us.
"I said to him before the (League Cup semi-final) game, 'Do not score' and he didn't. I hope that happens again."
Torres, who has scored 31 goals in 101 appearances for Spain, has played nearly 1,000 minutes in the Premier League since his last goal in the 8-0 win against Aston Villa.
He was left out of the Spain squad for the recent World Cup qualifiers against Finland and France.