The 41-year-old was part of the Owls side who won promotion from Sky Bet League One in 2012, which was the last time they featured in third tier of English football.
With Wednesday’s fate hanging in the balance, Llera believes it is imperative that they give it their all in the final game of the season against Derby at Pride Park.
He said: “They need to be in the Championship. This club is important for the city, it’s all about the fans, which is something I’ve known since my first game. It’s would’ve been difficult without them in the stadium because they are like a 12th player.
“The most important thing is, they’re still alive. The fans, the club and the players have to be together until the 95th minute to try and stay up. Whatever happens on Saturday, the club needs to be working towards next season.”
Llera says he really enjoyed his relationship with the fans during his time at Hillsborough.
“The connection was great, my personality and character fit really well to what the fans are looking for,” he added. “My passion and performances were something that’s expected from a Sheffield Wednesday player, because you need to make the club part of your life.”
If the club are relegated on Saturday, Llera believes only the players who are committed to getting the club back to the Championship should remain.
“They will need to figure out which players want to be at the club and play in League One, so they can bounce back like Hull," said Llera. “They would need to bring in people who will have a link with the fans and create a good environment.
“Having passion will bring happiness, if they don’t want to play then let them go. When fighting for promotion, everyone has to be on the same page with the same dream.”
Llera admits getting promoted in 2012 is one of the highlights of his career and hopes for a positive result on Saturday.
“It’s an amazing memory. Having 35,000 fans there was a moment of my career I’ll never forget. Hopefully the fans will be celebrating staying up this weekend."