ST. LOUIS -- The first time Willson Contreras seriously contemplated doing what was once unthinkable in a rivalry that dates to 1892 -- leaving the Cubs for the Cardinals -- occurred on Sept. 4, when the then-injured catcher looked on longingly at how Albert Pujols’ teammates and the Busch Stadium crowd celebrated the slugger’s 695th career home run.

Contreras, two months before becoming a free agent, marveled at the Cardinals' culture and how aging stars like Yadier Molina and Pujols were warmly embraced and celebrated.

Little did Contreras know at the time, but his interest in the Cardinals was just germinating. Another signature moment ultimately sealed his belief that St. Louis was where he wanted to be.

Following that Sept. 4 game at Busch Stadium, Molina -- the Cardinals' iconic catcher for 19 seasons -- autographed and penned a note on a jersey and had a clubhouse attendant deliver it to Contreras, who for years referred to Molina as “my idol.”

That’s where this Contreras story took a Hollywood-esque turn and sealed the catcher’s intentions of becoming a Cardinal. Upon returning to Chicago that night, Contreras slid his arms into the signed Molina jersey, tugged it across his chest and proudly buttoned it up. He showed it to his wife, Andrea.

“I did get chill bumps,” Contreras told MLB.com following his introductory news conference. “It was a nice moment I had with my wife, putting on that jersey. I asked her, ‘How do I look?’ She said I looked great, and I love the jersey even more now.”

From that moment, Contreras and agent Jose Mijares kept a major revelation to themselves. The gist: If all went well, the three-time All-Star would be a Cardinal in a few months.

“Yadier Molina sent the jersey to Willson and it said, ‘This is my last year, you are the future,’” Mijares said. “After seeing the celebration for Pujols, he later put the Yadi jersey on. He told me, ‘Jose, I know the money might be more in other places, but if you can make it happen with the Cardinals, I want to be a part of that.’ He was firm, and we got it done.”

Contreras, 30, was introduced as a Cardinal on Friday after he signed a contract that could run for six seasons. The Cardinals hold an option for the 2028 season that could extend the $87.5 million base beyond $100 million. Either way, Contreras got the most lucrative pact in Cardinals history for a player who had not previously played for the franchise. St. Louis is excited about having a catcher, a No. 5 hitter protecting Paul Goldschmidt and Nolan Arenado and someone with 22 home runs in ’22 who can replace Pujols’ retired thump.

Cardinals manager Oliver Marmol said the organization wanted someone with the fortitude to handle replacing Molina behind the plate.

“[Contreras] and Yadi are guys who earned respect, and they have that edge to where you don’t want to mess with them,” Marmol said. “Willson takes his job seriously, and he wakes up and goes to sleep thinking about winning. It’s an honor to come behind Yadi because he respects him. He said it perfectly: 'It’s an honor to [replace Molina], but I’m going to do it being myself.' He’s going about it the right way.”

Added president John Mozeliak: “You have that image of [Contreras] being someone you didn’t want to face with runners on and you thought of him as someone who could beat you. When you face them, you tend not to like them. … Speaking to him and seeing how he thinks about baseball was very enlightening.”

In addition to mentioning how impressed he was with Mozeliak and Marmol during a get-to-know-you summit in Orlando, Fla., Contreras stressed he’s excited to be a part of a Cardinals franchise focused on winning a World Series. He reached baseball's peak with the Cubs in 2016, but the core of that team ultimately fell apart. In St. Louis, he feels strongly he can win it all again.

“I knew I had to keep working and getting better, so I was ready when this opportunity came,” Contreras said. “I always wanted to do something every single day to get better even though [the Cubs] were rebuilding. … I’m excited for the next chapter, and I’m looking forward to beating the Chicago Cubs. I want to do everything I can to help the St. Louis Cardinals win it all.”