San Francisco 49ers head coach Kyle Shanahan joined The Adam Schefter Podcast on Monday and discussed the team's new franchise quarterback, Jimmy Garoppolo. Last month, general manager John Lynch confirmed what was widely assumed by the media and fanbase – Kirk Cousins, not Garoppolo, was always part of Shanahan's long-term master plan for the franchise's rebuild.

"We made the trade, but then there were some days that Kyle Shanahan was like in mourning because I think everybody knows his master plan was to have Kirk Cousins come in eventually," Lynch said during an ESPN Radio interview last month. "I was proud of Kyle because I think he knew this was the right thing for our franchise and he didn't hesitate."

How long was the "mourning" process for the 49ers head coach? He shared how much time it took to finally become entirely convinced that Garoppolo, and not another quarterback like Cousins, was the answer for his 49ers.

"It took about three weeks, to be honest with you," Shanahan told Schefter. "He had to go out there and play, and I thought we were in a good situation after our first year in terms of -- record-wise we weren't in a great situation, but I thought we were in a good situation to find a very good quarterback.

"Jimmy kind of fell into our laps for a second-round pick (traded to the New England Patriots) and I knew how talented he was from college, spent a lot of time on him (studying his film). We loved his two games we evaluated. So once we knew we could get him for a second-round pick, that's something that we would not have hesitated on.

"But then when we had him, the reason it took a few weeks was because we weren't going to lock ourselves into an unknown. We knew a guy, possibly like Kirk Cousins, was going to become available most likely in free agency. We also didn't have one win so we thought we might have the first pick in the draft and a bunch of good quarterbacks are coming out. So we knew we were in a good situation and we weren't just going to jump in (and say), 'Hey, we've got Jimmy. He's played in two games. Let's sign him long-term and just bypass maybe the first pick in the draft or someone like Kirk in free agency.'

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"So we just played it out [to] see what would happen. Jimmy went out there and played very well. In the first game, I was extremely excited. In the second game, I was even more excited. By the third game, I think we all kind of forgot about free agency and about the draft and we're like, 'Alright, we can isolate on one guy right now.' And we were very happy that it happened."

Shanahan also shared what he hopes to see from the 49ers and Garoppolo in 2018.

"I just want to improve," Shanahan said. "I think he played very well last year and everything went right. We hadn't won many games. We had only won one before he got in and we won five in a row with him. And that's a lot of success right there, but I know it's not going to be like that all this year. I'm pretty confident to say we won't go undefeated. If we do, congrats. I hope I'm wrong about that, but I'm not thinking that we will.

"And I'm looking forward to watching him play through a season. I know he's going to have some highs and I know he's going to have some lows and I want to see how he responds to it, how his teammates respond to it. Playing quarterback in this league isn't just about how talented you are and how good you are, it's how you can respond to all this pressure that really not many people can relate to except probably an NFL quarterback can."

Shanahan believes Cousins will see success with his new team, the Minnesota Vikings. Will he be everything the Vikings hope they got?

"He was on tape the whole time he was in Washington and will continue to be the rest of his career," Shanahan responded. "I think (with) most people, there's no doubt in that."

You can listen to the entire ESPN interview with Shanahan here.