The Blues face Arsenal in a Premier League summit clash on December 23, so Mourinho would prefer a straightforward encounter for his team against the Black Cats, managed by former Chelsea midfielder Gus Poyet.
"If Gus asks me for advice, I'll give him some advice," Mourinho said.
"He's playing (to avoid) relegation. He has to play the kids from the academy in our game and keep the guys fresh for the next weekend."
Arsenal are already out of the Capital One Cup after being beaten by Chelsea in the fourth round. Another win at the Emirates Stadium on December 23, this time in the league, will take Chelsea top of the table at Christmas.
"To play a game in the same week that you play second against first is a strange week, especially because Arsenal is not having this game," Mourinho said.
"I can guess that they are having a couple of days off. I can guess they are going to prepare the game calmly, tactically very well prepared.
"We have to travel, we have to play, we have to come back. But it's the quarter-final. When you are in the quarter-final, you smell the final. It's not very, very far. We are going to try."
Arsenal had their own fixture complaints last week, with their midfielder Mikel Arteta admitting he could not understand why the Gunners had to face Everton on a Sunday, followed by a Champions League clash with Napoli on Wednesday and then a lunchtime kick-off agsinst Manchester City on Saturday.
Mourinho twice won the League Cup during his first spell as boss. In a time when others sent in under-strength teams, he made the first serious trophy of the season a priority.
With strong opponents among the eight teams still in the draw - Manchester City at Leicester on Tuesday, while Wednesday's matches see Tottenham play West Ham and Stoke face Manchester United - Mourinho is not looking too far ahead.
He added: "We go to Sunderland, which is obviously very, very difficult, but on top of that you have Tottenham and West Ham, and Man United, Man City, it will be a difficult one."
Branislav Ivanovic is suspended after picking up a fifth caution of the season against Crystal Palace on Saturday, so Cesar Azpilicueta will switch to his preferred right-back position and Ashley Cole will return at left-back.
Mourinho is likely to make a number of further changes, with the prospect of a return for the rested Gary Cahill in central defence.
If Cahill features, John Terry will be given the night off.