The hosts are winless in this year's competition but would back themselves for success against a side that gained top-flight promotion this season.
Long-serving Varberg boss Joakim Persson has not tasted victory this season, and the winless run has left his side bottom of the Allsvenskan after 11 games.
The club from Halland County have lost six of their league games this term, with the raw numbers not giving reason for optimism.
The bottom side's soft underbelly is reflected in 22 goals conceded, while their absence of menace in the attacking third of the pitch is evidenced by seven goals scored.
They have netted only twice on their turf all season, letting in 12 in those games – a statistic that makes for grim reading heading into round 12's encounter this weekend.
The fact that 11 of the 12 conceded have come in the last three home games, having kept two clean sheets in their first three matches at the Varberg Energi Arena, does not bode well for their forthcoming encounter.
Varberg welcome Halmstad for the first time since the latter gained promotion at the backend of last season.
The visitors have had a mixed start to life on their return to the Allsvenskan, winning five and losing as many in 11 games (one draw), but they go into Saturday's fixture in better form than their hosts.
Not only are HBK unbeaten in their last three league fixtures, but Magnus Haglund's team have conceded just one goal in 270 minutes of football.
Halmstad have kept three clean sheets in five gameweeks — having kept one shut-out in the opening six rounds — a statistic that suggests they are finding their feet.
Thus, they possibly go into this weekend's game as the favourites to secure a positive result, and their recent form does not suggest otherwise.
Persson has utilised a back four and back three this term but is expected to approach this weekend's game with a 4-2-3-1.
Gabriel Wallentin could only make the bench against Hammarby, having gone off injured in the gameweek 10 fixture with Mjallby, and the Halmstad centre-back could make a return.
Viktor Granath is HBK's top scorer with four goals, and the forward could be the difference maker again against Varberg.
Varbergs BoIS possible starting lineup:
Lukic; Silverholt, Lindner, Stanisic, Nogueira; Karlsson, Le Roux; Alfonsi, Tranberg, Junior; Krasniqi
Halmstads BK possible starting lineup:
Nilsson; Ofosu-Ayeh, Johansson, Baffo, Olsson; Karlsson, Ahlstrand, Svedberg, Ammari, Allansson; Granath
We say: Varbergs BoIS 1-2 Halmstads BK
Having failed to pull up trees on their turf all season, Varberg are not expected to take anything from their encounter with Halmstad on Saturday, with the visitors likely to pick up their third consecutive road victory.
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