Just days afterAaron Rodgersannounced that he wasengaged, those close to the 37-year-old Green Bay Packers quarterback say they were shocked to learn that he and actressShailene Woodleygot so serious, so fast.

“It was a surprise that they got so close so quickly,” a source close to the athlete tells PEOPLE in this week’s issue. “I mean, it really felt like one day he was withDanica Patrick, and then suddenly he was with Shailene. It happened super fast.”

Insiders say that Rodgers and Woodley immediately clicked over the summer and began spending a lot of time together.

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“It was so fast that at first, we thought she was just a rebound,” says the source close to Rodgers. “There was no way this could be so serious. Everyone thought it was a casual thing because that’s what he was telling everyone, even when it was clearly not a casual thing.”

While making a virtual appearance during the NFL Honors broadcast on Feb. 6, Rodgers gave his fiancée a shout-out as heaccepted the NFL MVP award.

“It’s an honor to win this award for the third time. 2020 was definitely a crazy year filled with lots of change and growth, some amazing memorable moments. 180 straight days of having my nose hair scraped, playing for very little fans or no stands the entire season,” he said, before revealing the big news: “I got engaged.”

Rodgers went on to thank his loved ones, including his future wife.

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Just days before the NFL Honors event, multiple sourcesconfirmed to PEOPLEthat Rodgers has been dating Woodley. One source told PEOPLE that Rodgers seems very happy with the 29-year-oldBig Little Liesstar.

“Now we realize that it was clearly a lot more serious than they told anyone,” says the source to PEOPLE. “All this goes to show that this must be a very special relationship for him and for her. So everyone wishes them happiness.”

source: people.com