The 27-year-old academy product has scored just 15 goals in 67 appearances in the 18 months since signing a big-money deal until 2028, with speculation over his future increasing in recent days.
Rashford was the main topic at the press conference nominally previewing that tie, with Amorim saying he was keen to keep a player he had yet to speak to by the time he faced the media.
"It's hard to explain to you guys what I am going to do (when I speak to him)," United's head coach said. "I am a little bit emotional (as a person), so in the moment I will understand what to do.
Marcus Rashford is expected to miss the Carabao Cup clash with Tottenham
"I am preparing the game and then we will see. Let's focus on the team not individual players. That's it."
When asked if he would air his views publicly in an interview or speak to the manager privately, the former Portugal international said: "If this was me, probably I will speak with the manager.
"But, guys, let's focus on Tottenham. Tottenham is the most important thing."
Amorim let out a laugh at the end of that final answer of a 14-minute press conference that featured 16 different questions about Rashford in the wake of an interview that PA understands took United by surprise.
"It's a hard situation to comment (on)," the head coach said after being quizzed about his handling of it.
"If I give a lot of importance, it will have big headlines in the newspaper. If I say it's not a problem, then my standards are getting low.
"So, I will deal with that, I understand that. My focus is not to take the attention from the game, from the team, what we did in the last game and put on Marcus.
"What I'm saying is that the team is more important than the individual. We will assess at the right time, let's focus on the game. That's all."
Amorim repeatedly said his focus was on the cup clash with Spurs as he pushes for more, which is what he indicated on Sunday he wanted from Rashford and Alejandro Garnacho.
The Argentina international was another surprise absentee from the Manchester derby but has been pictured with the group heading south to take on Tottenham having reacted impressively.
Ruben Amorim is happy with Alejandro Garnacho’s response
"Really good, he trained really well," Amorim said. "He seems a little bit upset with me and that is perfect.
"I was really, really happy because I will do the same (in his position) and he's ready for this game."
Amorim insisted on Sunday that there were no disciplinary issues behind his decision to leave Rashford or Garnacho out of the derby.
In addition, a United source told PA that the latter's absence had nothing to do with allegations about team leaks.
Club staff have reportedly spoken to some players about the line-up getting out, as it did on the eve of the Manchester derby, but the head coach is taking a laissez-faire approach.
Asked if he was going to do anything in a bid to prevent further leaks, Amorim said: "Nothing.
"Nowadays all the coaches know about it because I explained a lot about the team, the way I want us to play, the positioning, etc.
"But I say that because I understand that the coaches have that information just to see one time Manchester United play, so I'm not really worried about that.
"I also cannot control that, so I will do the same things, prepare the same way, because for me it's more important for my players to go to the game with a clear idea of how to do it than try to hide something to protect the leaking of the starting XI.
"That is not my focus. I'm not really worried about that."