Jones was named the team's new starter on Tuesday, and Manning knew that the possibility had existed since the Giants drafted Jones with the sixth overall pick.
"In some ways I signed up for this, knowing when you draft a young quarterback, this can happen," Manning said. "And I gotta live with it and make the best of it."
That means serving as the backup and a sounding board for Jones, effective immediately. Manning, who was standing in front of his locker waiting for the media, mentioned having to get used to handling duties such as running the scout team.
It's quite a change. Except for one week, Manning has been the Giants' starter since midway through the 2004 season. It seems unlikely that the two-time Super Bowl winner will finish his career elsewhere.
Manning, 38, has a no-trade clause in his contract. Two sources close to the quarterback said this week that they didn't expect him to wear another team's jersey and believed he would eventually retire as a Giant.
When asked whether this was the end of his time with the team, Manning expressed uncertainty.
"Who knows. Again, I'm not dying, and the season's not over," he said. "So there's a lot to be positive about, a lot to be grateful for, and so I just gotta accept my new role and make the best of it."
Manning was informed of the change by coach Pat Shurmur, who said the decision was his but that he also consulted general manager Dave Gettleman and ownership.
Manning, who also spoke with co-owner John Mara, said he didn't have any complaints about the way the situation was handled.
"So everything's been good and, I guess, as positive as it can be," Manning said.
The Giants told Manning before drafting Jones in April that the veteran would be the starter as long as he won games. The team has started 0-2 for the sixth time in seven years.
"Again, I'm not going into all that," Manning said when asked whether he was misled. "I think it's just one of those deals you ... This is the situation. You deal with it, and that's what I'm doing."
Jones, who will make his first career start Sunday on the road against the Tampa Bay Buccaneers, was excited to receive the news. He was also appreciative of the support he received from Manning.
"I think [Tuesday] when Coach Shurmur told me, and obviously Eli as well, I think we had a conversation. And as y'all would expect -- as anyone who knows Eli would expect -- [he was] nothing but supportive of me," Jones said. "And, obviously, I understand the circumstance, and it's a difficult one. But he was very supportive of me, and I can't say enough about who he is as a person, as a teammate, and he's been that way since I've gotten here.
"We had that conversation, and then we went about our Tuesday, preparing and watching film like we have the first two weeks. I'm certainly very grateful and appreciative of his support since I've gotten here."
The Giants have said since the summer that they were getting Jones ready to play. Offensive coordinator Mike Shula even said in the spring that he thought the rookie was capable of starting Week 1.
The clock was ticking. Shurmur admitted he'd thought of making the change immediately after Sunday's 28-14 loss to the Buffalo Bills.
Shurmur said the decision was made under the premise that he believed Jones gave the Giants the best chance to win.
"Daniel Jones is ready to play, and we're going with him. Yes," Shurmur said. "And the reason I say that is because we do everything we can to win football games, and at this point, we feel like he's the guy we wanna move forward with."
Eli: Have to accept my role and make the best of it
Eli Manning contends losing his starting QB job to Daniel Jones isn't the end of the world and he will do anything to help the Giants be successful.