OAKLAND -- In addition to three Minor League clubs that already held an affiliation with the Athletics, a new team was invited to join the organizational fold for the 2021 season.

The A’s announced Wednesday they’ve extended invitations to four Minor League clubs to become Oakland’s affiliates under MLB’s new player development structure. Among the familiar faces are the Triple-A Las Vegas Aviators, Double-A Midland RockHounds and Class A Stockton Ports. The Lansing Lugnuts have been invited as the High-A affiliate, swapping with Stockton, which would move to the Low-A level.

"On behalf of the A's, I am excited to invite four outstanding organizations to partner with us under MLB's new player development structure," A’s general manager David Forst said in a statement. "We are proud to have already been affiliated with three of these communities and are thrilled to welcome another into the A's player development family. We know how much minor league baseball was missed in 2020 and look forward to A's minor leaguers playing in Las Vegas, Midland, Lansing, and Stockton for many years to come."

• Tracking new Minor League affiliates for 2021

Lansing was formerly an affiliate of the Blue Jays, often squaring off against Oakland’s former Midwest League affiliate, the Beloit Snappers. While other cities were in play for the A’s, Forst pointed to a recently renovated stadium and proximity to Michigan State University as a couple of the features that made Lansing an attractive option.

“More than anything, it’s a great organization,” Forst said in a Zoom call Wednesday. “I had a great conversation with [Lansing] owner Tom Dickson. “As long as we’ve been in the Midwest League, Lansing has really been a desirable spot. It’s a great ballpark. It’s a college town and a really good city for players to be. We were happy that it worked out the way that it did.”

The reclassification of the entire California League, which includes Stockton, is a notable change. Often a destination for some of the club’s top prospects for a chance to play in close vicinity to the big league club -- about 65 miles from the Oakland Coliseum -- Forst said he is unsure how Stockton’s transition to Low-A will affect the distribution of players. Some of those top prospects could end up in Lansing, though the A’s still plan to utilize Stockton heavily for rehab stints with Major League players making their way back from injury.

“Guys who were in the Midwest League in 2019 may end up there again in 2021. There are so many things we don’t know about how missing an entire year will affect the development of some of these players,” Forst said. “We’ve made some adjustments on the staff based on the High-A and Low-A classifications. It will definitely affect the players that we send to both places. All that needs to be ironed out as we get into the spring.”

As part of the new structure, Oakland loses its affiliation with the Short Season Vermont Lake Monsters, an A’s farm club since 2011. Vermont was often the entry port for many young A’s prospects who had just been drafted to get their feet wet. Many of those young players who would have gone to Vermont this upcoming season will now head to Arizona, where the club will set up the Arizona League A’s that will be based out of the club’s Spring Training complex in Mesa.

“No longer being affiliated with Vermont is certainly one of the sad parts of this process,” Forst said. “When we first ended up in Vermont, you couldn’t have been geographically further away, but it ended up being a great relationship. I feel badly that we’re no longer sending players to Vermont, but everyone is going to have to adjust.”