The Sydney Roosters are refusing to take their eye off the ball just as an improbable NRL finals berth edges closer to reality. Written off and languishing in 13th spot barely a month ago, suddenly the Roosters are equal eighth on the ladder and as close to having their finals destiny in their own hands as they could have hoped for. They still may need a touch of luck but a victory over bottom-placed Wests Tigers at Allianz Stadium on Saturday will set up a likely do-or-die last-round encounter with South Sydney for a finals spot. Fans of the two arch-rivals - and even neutrals - are already salivating at the prospect of another bitter derby to determine their seasons' fate. The Rabbitohs ended the Roosters' campaign last year in an infamous finals battle featuring a record seven sin-binned players. The Roosters, though, have eyes only for the Tigers, who will be equally desperate to win after a drought-breaking victory over the Dolphins raised hopes that the joint venture can somehow avoid a second straight wooden spoon. Roosters back-rower Nat Butcher on Monday said his side's rivalry with Souths always made for compelling viewing, but thoughts this week were firmly on the Tigers. "Obviously the rivalry (with Souths) is there, and every year it's so competitive and always does feel like a finals game, but that's next week," he said. "This week we've got the Tigers in, so we just got to focus on that. "I've been watching the Tigers a bit throughout the year. They're a good team. They play hard, they're very physical. They've beaten Penrith throughout the year." With a loss to the Tigers likely killing off the Roosters' finals hopes, Butcher insisted there was no need to address potential complacency this week. "All the boys, we're all level headed and we know that we've still got to win this week, as it was last week and the week before that," he said. "They had a good win on the weekend so they'll be coming into the game with a bit of momentum and we've got to show them the respect that they deserve and be at our best." The Roosters are resigned to being without inspirational skipper and former Tiger James Tedesco, who suffered yet another category one concussion in last Thursday's 34-12 win over Parramatta. But they have a ready-made fullback replacement in reigning world player of the year Joey Manu to fill the void of the NSW and Australian captain. Butcher said Manu was a more than able substitute. "He's such a great player what he does for New Zealand and then when we do get him for a couple of weeks, throughout that Origin period there at fullback, he really executes his role," he said. Sign up for our emails