Twentieth in the standings with just eight wins and 29 points from 26 games, the Millers are just a point above the drop zone.
However, it doesn't tell the full story. Some improved results in the new year have seen the side climb out of danger.
Four wins and a draw from the last six games have seen them go up from 22nd in the standings. However, manager Paul Warne still has plenty left to do.
Cardiff haven't impressed much either, but they're safe in 14th place, with 34 points. New manager Mick McCarthy has managed to arrest their downward spiral for the moment.
A run of five consecutive losses, which plunged the side from ninth down into the bottom half of the table, saw Neil Harris given the axe. McCarthy has so far overseen two draws and a win.
That victory came away to Bristol City last weekend, their first in eight games.
Rotherham United vs Cardiff City Head-To-Head
In 48 games, Rotherham have won 22 times, while Cardiff have claimed the spoils on just 13 occasions.
That includes wins for Cardiff in each of the last two clashes, coming during the 2016-17 season in the Championship.
Rotherham United Form Guide (all competitions): D-W-L-W-W
Cardiff City Form Guide (all competitions): L-L-D-D-W
Rotherham United vs Cardiff City Team News
Chiedozie Ogbene is the only major concern for the home side. The left winger has been out since September last year and continues his recovery from a knee injury.
Injured: Chiedozie Ogbene
The Bluebirds will be without Sol Bamba. The centre-back was diagnosed with lymphatic cancer last month and has begun treatment.
Unavailable: Sol Bamba
Rotherham United vs Cardiff City Predicted XI
Rotherham United (3-5-2): Viktor Johansson; Michael Ihiekwe, Angus MacDonald, Clark Robertson; Wes Harding, Lewis Wing, Dan Barlaser, Ben Wiles, Ryan Giles; Matt Crooks, Michael Smith.
Cardiff City (3-4-1-2): Dillon Phillips; Sean Morrison, Aden Flint, Curtis Nelson; Perry Ng, Will Vaulks, Joe Ralls, Joe Bennett; Harry Wilson; Sheyi Ojo, Kieffer Moore.
Rotherham United vs Cardiff City Prediction
Rotherham have improved slightly under McCarthy and will be confident of a win, but Cardiff have the capacity to force a share of the spoils.
Prediction: Rotherham United 1-1 Cardiff City