Holmes extinguished the Tigers' comeback when he scored his second try, picking up a loose ball to go 60 metres to score next to the posts before Wade Graham and fullback Michael Gordon, who was one of the Sharks' best, both scored late tries.
Gordon finished the day with 16 points, kicking a penalty goal and five from six conversions.
The Sharks went to the halftime break leading 20-6, following a dominant opening from the hosts.
Jason Taylor's side hardly had their hands on the ball in the first half and, when they did, they usually dropped it.
Luke Lewis opened the scoring after four minutes when he steamed onto a flat pass from Jack Bird before the Tigers hit back against the run of play with Tim Simona scoring.
The try came one tackle after halfback Luke Brooks produced a one-on-one steal before setting off on a 95-metre run.
Cronulla answered with tries to Sosaia Feki and Michael Ennis.
The defeat leaves the Tigers on 18 points and equal with the last-placed Gold Coast.
-AAP