Manly Sea Eagles kept the heat on National Rugby League leaders Melbourne with a grinding 12-8 win over Penrith on Sunday. The Sea Eagles hover two points behind the Storm with victory sealed 15 minutes from time following a runaway Keiran Foran try. Melbourne rung up their eighth successive win with a hard-fought 26-6 victory over Brisbane Broncos at home on Friday. The last time the Storm won eight games straight was in 2007 on their way to a premiership that was stripped last year when salary cap cheating was exposed. A frenetic match was in the balance until the 57th minute when Melbourne winger Justin O\'Neill dived across in the corner for a clinching try. Champions St George Illawarra will attempt to keep in touch with the top two if they can beat the Raiders in Canberra in the remaining match of round 20 on Monday. North Queensland Cowboys kept above the Broncos in fourth spot on points differential after a gripping 28-20 win over lowly Gold Coast Titans on Saturday. Forward Gavin Cooper went from villain to hero for the Cowboys after an embarrassing blunder late in the first half when he fumbled the ball over the Titans\' try-line. But with the Titans clinging to a 20-18 lead Cooper redeemed himself with a scrambling try before Cowboys centre Willie Tonga sealed the win with his 76th-minute try. Giant New Zealand Test winger Manu Vatuvei claimed a hat-trick of tries as the Warriors all but ended South Sydney\'s season with a 48-16 mauling at the Olympic stadium on Sunday. The Warriors ran riot in a nine tries to three thrashing of the injury-ravaged Rabbitohs to hold down sixth place. Wests Tigers consolidated their top-eight spot with a hard fought 19-12 win over Sydney Roosters at Leichhardt Oval, while Newcastle Knights moved to eighth spot with a slogging 18-0 win at Cronulla. A 41-metre drop goal from Trent Hodkinson gave the beleaguered Canterbury Bulldogs an 8-7 golden point extra time win over Parramatta to deliver caretaker coach Jim Dymock his first NRL victory.