"If I play, I won't be starting. Ninety minutes is too much for my first match. We're taking it day by day so we still have one more day to see how I do," Morgan told a news conference on Friday.
"I'm really hopeful to get on the field soon. This weekend will obviously be two weeks of me completing training so we're taking it day by day. I obviously have to look at the time I've been out, the fact that my body needs to get back to full fitness.
"We've had a flexible plan starting with the first day I was here and looking at when I could get into my first game and how many minutes and I've had quite a few meetings with our fitness coach and head coaches and continue to talk about that but obviously no one wants to see my in a game more than myself."
The two-time World Cup winner joined Spurs from Orlando Pride but hasn't played a competitive game since giving birth to her daughter, Charlie, in May.
Morgan joined Spurs on the final day of the WSL transfer window and said her decision was spurred on by a number of factors including the coronavirus pandemic.
"I joined spurs because I feel like the WSL has done such a good job bringing over such great talent and competing as one of the top leagues," she added.
"I also felt like in the U.S. right now it's quite uncertain with the pandemic and here I'm very comfortable with the playing situation and with the uncertainty over the NWSL year, I think that after pregnancy I needed to get as many games in as possible leading to 2021 knowing that the Olympics will hopefully be on next year.
"I wanted to make sure to put myself in the best position possible to get ready for that and I thought that competing in one of the best leagues in the world right now while it started back up after lockdown was the best option for me. Joining Spurs was important to me because it's such a good organisation."
Morgan's contract with Spurs runs until December. She has the option of extending it until the end of the season, but she said she didn't see it becoming a multi-year deal.
"I think for right now we're keeping our options open. I want to help the NWSL continue to grow," she said.
"I'm excited to see out to December and maybe further."