The two sides shared the spoils on Tuesday night with a 1-1 draw at the Stadium of Light.
The result leaves Rotherham needing a win against Gillingham on the final day of the campaign to secure their automatic promotion.
However, dropped points against The Gills would open the door to MK Dons which could leave Rotherham in the play-offs instead.
Warne believes Sunderland will be the team his side wants to avoid should they both end up in the promotion shootout.
“We knew when we came here that Sunderland and Wycombe are probably the two in-form teams at the moment,” said Warne, via The Northern Echo.
“I obviously don’t want to drop into the play-offs, but if we did, I wouldn’t want to play Sunderland home and away.
“I know they made changes for this game, and respectfully, I think they made changes because they knew the energy and pace we had. So, to limit them to very few chances was good.
“But when you’ve got 35,000 people cheering you on, it makes a difference. I appreciate you might get the odd decision here or there, as I would want if I had 35,000 at my place.
“I thought we deserved to win the game, but I accept that I’m biased. I have the utmost respect for Alex and his team, and I thought they played really well against a really good League One team.”
Quiz: Did Rotherham United sign these 26 players for a fee or a free?
Meanwhile, Sunderland need a win on the final day of the regular season as they face Morecambe.
Dropped points could open the door for Wycombe Wanderers to leapfrog Alex Neil’s side in the League One table, leaving the Black Cats in 7th place.
The final round of games take place on April 30, with a kick-off time for all games of 12.30pm.
Sunderland are going into the final game against Morecambe with a 12-game unbeaten run.
That kind of form has helped cement the side inside the top six before the last game of the season.
But the play-off race is still extremely competitive, and it is remarkable that this unbeaten run hasn’t secured a top six finish already.
But if they can defeat Morecambe on Saturday then Neil’s side will certainly have a lot of momentum going into the final crunch games of the campaign.