Goals from Michael Wylde and Danny Meadows helped Alfreton beat Southport for their fourth successive win.
Wylde put the home side ahead midway through the first half when he steered in Paul Clayton's low cross.
Danny Meadows then converted a right-wing cross from Dan Bradley to double their advantage on the half-hour mark.
Richard Brodie pulled a goal back 14 minutes from time and Alfreton keeper Jon Worsnop secured the points with a late save to deny Scott Brown.
Southport have not won any of their last seven league games and are now only one point above the Conference Premier relegation zone.
Alfreton remain third in the table, seven points behind leaders Luton Town.
VIEW FROM THE DRESSING ROOM
Alfreton manager Nicky Law told BBC Radio Derby:
"I think it could have been a lot more convincing in the first half, so we spoke at-half time about needing to step the tempo up.
"But credit to the players, we've had four tough games with heavy pitches and with the injuries and suspensions we've got, it's the same group that are having to do it all the time.
"We're disappointed in the goal that we gave away, even though they were chucking everything at us. I can't fault the lads at all though, because what they're doing is fantastic and hopefully we can keep doing that."
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.