Tasman currently sit fourth in their conference but will be overtaken by Northland on Sunday if the Taniwha beat winless Manawatū at home.
The Mako have only themselves to blame after falling to their sixth loss in 10 games, though Hawke's Bay certainly deserve credit for inflicting tonight's defeat.
The hosts could have had revenge on their minds after last year seeing their season ended by Tasman in the semifinals, but this victory was more clinical than emotive.
It was built, like many of their wins have been, on an effective set piece, with their lineout leading to three tries in the first half.
The first was scored in the opening moments by Tyrone Thompson, capitalising on the decision to kick for the corner with yet another rolling-maul try.
The second looked like it would come in similar fashion but, with the drive stopped short of the line, Danny Toala dinked a cross-kick for Neria Fomai to collect and cross.
And the third, coming after the Mako had hit back through a lightning-quick attack down the left finished by Noah Hotham, saw Marino Mikaele-Tu'u make it 17-10 on the stroke of halftime.
Having been comprehensively beaten up front in the first half, Tasman at least fought the set-piece battle to a draw in the second spell, though that rarely threatened to change the outcome.
Formai's second try put the hosts in complete control and, despite the Mako enjoying large spells in possession, the Hawke's Bay defence held firm until Viliami Napa'a scored a late consolation.
Hawke's Bay 25 (Tyrone Thompson, Neria Fomai 2, Marino Mikaele-Tu'u tries; Lincoln McClutchie con, pen)
Tasman 17 (Noah Hotham, Viliami Napa'a tries; Taine Robinson pen, con, Willy Havili con)
Halftime: 17-10
