The man Roosters legend Brad Fittler believes is most capable of troubling his old team's NRL-best defence in Saturday's preliminary final at Allianz Stadium is a former Rooster himself – Joseph Leilua.
The 21-year-old Knights centre, who was released by the Roosters late last year because of disciplinary reasons, is in crazy-good form at the business end of the season.
Overall, Leilua has played 18 games in 2013, scoring 11 tries and making 12 line-breaks and 11 offloads.
He has run for over 100 metres in 12 games, including his last 10 straight, and his influence on the Knights' fortunes has continued to grow.
In the 26-18 win over the Broncos in Round 25, Leilua ran for 136 metres and scored two tries, as well as making two line-breaks and one offload.
In the final round, when the Knights thrashed the Eels 54-6, Leilua again scored two tries and made two line-breaks as he ran for his season-best 179 metres.
Leilua hasn't scored a try in the finals series yet, but he has continued to be a massive threat in attack; by forcing multiple defenders to commit to trying to stop him he has made it easier for the fellow attacking players around him to do something.
Against the Bulldogs in the first week of the finals, when the Knights won 22-6, Leilua ran for 141 metres and contributed one offload.
And last weekend, in the 18-16 win over the Storm, he ran for 166 metres and had one offload.
Defences are struggling to stop his progress, and when they do manage to slow him down they then have to try to guard against him getting the ball away, which he is doing with increasingly greater effect just out of sheer practice on the field.
Leilua made his first grade debut for the Roosters as an 18-year-old in the 2010 season.
He didn't become a regular first-grader that season, but when the Roosters made the grand final and had injury issues coach Brian Smith selected the youngster on the wing for the decider against St George Illawarra.
The rookie found it difficult under the massive pressure that evening, but with experience he has grown into a much more self-assured player on the field, and has begun to mature off it as well.
The learning process continues – Knights coach Wayne Bennett had to speak to Leilua about his sledging of Storm forward Jordan McLean after McLean had been knocked out in an accidental head clash in last weekend's game – but the sky is the limit for him.
Fittler, who captained the Roosters to their last grand final win, in 2003 against the Warriors, is certainly impressed by the power Leilua displays on the field.
"He's just so strong," Fittler said. "I mean, just look at him play. He's got that ability to give the defence a really hard time.
"As well as the Roosters have defended this season, Leilua is someone they're going to have to worry about."
The Roosters went straight from Week One to Week Three of the finals series by virtue of their 4-0 win over Manly at Allianz Stadium.
Fittler liked what he saw that night from the Roosters, in what was a brutally defensive display from both teams, but says they can't afford to rely solely on their defence to get them to the grand final and then win it.
"I thought they were great against Manly, but the way the game went probably disguised what they need to do a bit more of from here," he said.
"They've got to score more points, so that they've got that balance on both sides of their game.
"The way I look at it, there wasn't much between the last four teams in the competition going into this weekend. They all looked pretty good to me.
"I think the only real difference, if the teams that didn't play last weekend could make it work for them, was the fatigue factor for the teams that did have to play last weekend."
The Roosters will obviously be looking for superstar second-rower Sonny Bill Williams to come up with a big play or two against the Knights.
"He's looking pretty fit," Fittler said. "He's a big-game player."
Fittler paid tribute to his former NSW teammate, Knights hooker Danny Buderus, who is retiring at the end of the season.
"He's a wonderful person and he's been a great player over a long period of time," Fittler said. Then he added, with a smile: "I think that playing in the preliminary finals would be a wonderful way for 'Bedsy' to go out."
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