The Sharks leapfrogged Fremantle Roosters into second place with a 24-16 victory at Ken Allen Field last Saturday, with goal kicking the difference between the two sides.
Reggy Manu opened the scoring, crossing the line inside five minutes to put the Sharks ahead, which they extended to 16-0 just before half- time.
However, the Roosters pegged them back with two tries before the siren to cut the lead to 16-8.
The second half started as the first ended, with Fremantle piling on the pressure.
Rockingham�s defence stood firm but the defensive wall finally cracked after some great organisation of the play by Roosters� captain/coach Delane Edwards.
With 20 minutes to go, the Roosters scored twice to level the scores, before Josh Neal kicked a 40-metre penalty to restore the Sharks� lead.
The Sharks secured victory in the final 10 minutes, crossing for their fourth try. It was converted by Neal, who missed only one of his five shots at goal, while the Roosters failed from all four of their conversion attempts.
Among the best players for the Sharks were prop Ryan Wilson, who scored two tries, Tane Peakman, Andrew Jeffreys and debutant Neal.
The Sharks face North Beach tomorrow at Franklin Offshore Sportsplex, Lark Hill, and a win will secure second spot, which means a second chance in the finals.
Fremantle can reclaim second from the Sharks if they beat Joondalup and Rockingham lose. The Sharks� opponents have secured fourth spot and are coming off a 70-22 thrashing of Kalamunda.
In other games last week, the Sharks reserves and third grade sides won 40-6 and 30-14 respectively, while the under 18s lost 34-28 and the women�s league tag lost 28-0.