PORTLAND, Ore. – A day after announcing they were investing in a group trying to bring Major League Baseball to Portland, Russell Wilson and Ciara visited the Rose City to check out potential sites for a stadium.

The Seattle Seahawks quarterback and pop star said they flew over four potential stadium sites on Saturday. Only three sites have been publicly disclosed: Portland Public Schools’ headquarters, ESCO Corporation’s industrial site, and the Port of Portland’s Terminal 2.

More: Portland baseball group inquires about third site for MLB stadium

Wilson and Ciara, who are married, said they had a clear favorite but didn’t specify which one.

Members of the Portland Diamond Project have been quietly working for months to build a baseball stadium and lure a professional team to Portland. Craig Cheek, the founder of Portland Diamond Project, approached Wilson with the investment pitch. The two knew each other from when Cheek worked at Nike and signed Wilson to a sponsorship deal.

Wilson said his decision to invest in Portland Diamond Project took no convincing from Cheek.

“I’m very particular about what I get involved in…it was a no-brainer,” Wilson told reporters during a news conference at Baseballism in Northwest Portland on Saturday.

Watch: Russell Wilson, Ciara talk about bringing MLB to Portland

Wilson, who played professionally in the minor leagues, said baseball is “near and dear” to him and has always had aspirations of owning a team.

Wilson and Ciara invested individually and both would be minority owners if Portland lands a team. It's not clear how much they are investing in the project.

Photos: Singer Ciara and Seahawks QB Russell Wilson

Ciara would join a small group of African-American women to have ownership in a professional sports franchise.

“Honestly, it’s very special. It means a lot," she said on Saturday. "Like I said, not only for myself but for other young girls and young women around the world because the truth is we can really do anything we put our minds to."

Wilson and Ciara hope they can help build a culture that engages with all fans.

“The reality is…there’s not that many African-Americans in baseball,” Wilson said. “One of the things that I’ve thought about is how can we get people involved? How can we do that for all kids, all races, all people?”

MLB in Portland: What we know

For a stadium, Wilson said he wants it near the water and to have a neighborhood feel. He cited Providence Park, and said he wants to re-create the energy at Timbers games for a baseball team.

“Baseball deserves that. Baseball needs that and we can do that here in Portland,” he said.

Ultimately, they said their hope is to put a winning team on the field that creates a special bond with a special city.

“It’s just been an incredible journey living in the Pacific Northwest and the idea of this also being our home also sounds pretty cool to me,” Ciara said.

“For me and Ciara and our whole team that’s trying to bring baseball to Portland, there’s really no better place,” Wilson said.

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