Helensburgh claimed top spot on the Illawarra Coal League ladder with an impressive 25-0 victory over northern rivals Thirroul at Gibson Park on Sunday.

Two tries in the five minutes before half-time proved the killer blow for the Tigers after a ferocious first half in which there were no points scored for 35 minutes.

Tigers five-eighth Jarrod Boyle was instrumental in the victory, scoring the first try of the match and laying on another on the stroke of half-time.

"I thought we had a pretty good first half and we were a bit scratchy in the second half but gee we turned up for each other," Tigers coach Ryan Powell said.

"Thirroul threw a bit at us there when we didn't respect the ball but we were good enough to hold on.

"We knew nothing was going to be the easy way today; it was a top-of-the-table clash and deservedly so, the footy showed it.

"I think the zero was the best part of it. Thirroul had enough ball to put some points on but we just kept turning up and that's a credit to the guys."

As half-time loomed and the scoreboard untroubled, a Hillen kick deflected off a Butchers defender and into the arms of winger Wayne Bremner, who launched a wobbly bomb that saw Boyle leap over Butchers fullback Sam Clune for the first try of the match.

Boyle featured again moments later with a cut-out ball that put back-rower Chris Lewis into space and allowed Azan Turoa to finish in the corner, setting up a 12-0 lead at the break.

The Tigers extended their lead when dummy half Dan Fepuleai earned penalty in front of the posts.

The Burgh landed the telling blow with 20 minutes to go when second-rower Blake Phillips put Bremner away down the left flank. Bremner found Hillen on the inside for the Tigers third try.

Boyle put the result beyond doubt with a 40-metre field goal with five minutes left before Jason Raper scored a late try to bring the final score to 25-0.

It was the second straight loss for the Butchers, who were without captain Nathan Fien due to a niggling calf injury and lost their other chief playmaker Nathan Wynn to a hand injury early in the match.